diff --git a/apps/central-scan/backend/src/interpreter.test.ts b/apps/central-scan/backend/src/interpreter.test.ts
index 6c828c5a7e..46055acbfc 100644
--- a/apps/central-scan/backend/src/interpreter.test.ts
+++ b/apps/central-scan/backend/src/interpreter.test.ts
@@ -962,7 +962,7 @@ test('interprets marks in ballots', async () => {
           Object {
             "id": "write-in-0",
             "isWriteIn": true,
-            "name": "Write-In",
+            "name": "Write-In #1",
           },
         ],
       }
@@ -2028,7 +2028,7 @@ test('returns metadata if the QR code is readable but the HMPB ballot is not', a
           Object {
             "id": "write-in-2",
             "isWriteIn": true,
-            "name": "Write-In",
+            "name": "Write-In #3",
           },
         ],
       },
diff --git a/apps/central-scan/backend/src/types.ts b/apps/central-scan/backend/src/types.ts
index 5c61648262..8b1f558505 100644
--- a/apps/central-scan/backend/src/types.ts
+++ b/apps/central-scan/backend/src/types.ts
@@ -1,11 +1,4 @@
-import {
-  BallotLocale,
-  BallotMark,
-  BallotTargetMark,
-  MarkStatus,
-  MarkThresholds,
-  PageInterpretation,
-} from '@votingworks/types';
+import { BallotLocale, PageInterpretation } from '@votingworks/types';
 import { BallotStyleData } from '@votingworks/utils';
 
 export interface PageInterpretationWithAdjudication<
@@ -25,25 +18,3 @@ export interface BallotConfig extends BallotStyleData {
   locales: BallotLocale;
   isLiveMode: boolean;
 }
-
-export function getMarkStatus(
-  mark: BallotTargetMark,
-  markThresholds: MarkThresholds
-): MarkStatus {
-  if (mark.score >= markThresholds.definite) {
-    return MarkStatus.Marked;
-  }
-
-  if (mark.score >= markThresholds.marginal) {
-    return MarkStatus.Marginal;
-  }
-
-  return MarkStatus.Unmarked;
-}
-
-export function isMarginalMark(
-  mark: BallotMark,
-  markThresholds: MarkThresholds
-): boolean {
-  return getMarkStatus(mark, markThresholds) === MarkStatus.Marginal;
-}
diff --git a/apps/central-scan/backend/src/util/option_mark_status.ts b/apps/central-scan/backend/src/util/option_mark_status.ts
index bdab85cd3d..75d928674a 100644
--- a/apps/central-scan/backend/src/util/option_mark_status.ts
+++ b/apps/central-scan/backend/src/util/option_mark_status.ts
@@ -6,7 +6,7 @@ import {
   MarkThresholds,
 } from '@votingworks/types';
 import { throwIllegalValue } from '@votingworks/basics';
-import { getMarkStatus } from '../types';
+import { getMarkStatus } from '@votingworks/utils';
 
 /**
  * state of the mark for a given contest and option
@@ -29,13 +29,13 @@ export function optionMarkStatus({
     switch (mark.type) {
       case 'candidate':
         if (mark.optionId === optionId) {
-          return getMarkStatus(mark, markThresholds);
+          return getMarkStatus(mark.score, markThresholds);
         }
         break;
 
       case 'yesno':
         if (mark.optionId === optionId) {
-          return getMarkStatus(mark, markThresholds);
+          return getMarkStatus(mark.score, markThresholds);
         }
         break;
 
diff --git a/apps/scan/backend/src/types.ts b/apps/scan/backend/src/types.ts
index 243ed0b301..c157740fe6 100644
--- a/apps/scan/backend/src/types.ts
+++ b/apps/scan/backend/src/types.ts
@@ -1,8 +1,6 @@
 import {
   AdjudicationReasonInfo,
-  BallotTargetMark,
   ElectionDefinition,
-  MarkStatus,
   MarkThresholds,
   PageInterpretation,
   PollsState,
@@ -31,21 +29,6 @@ export interface BallotPageQrcode {
   position: 'top' | 'bottom';
 }
 
-export function getMarkStatus(
-  mark: BallotTargetMark,
-  markThresholds: MarkThresholds
-): MarkStatus {
-  if (mark.score >= markThresholds.definite) {
-    return MarkStatus.Marked;
-  }
-
-  if (mark.score >= markThresholds.marginal) {
-    return MarkStatus.Marginal;
-  }
-
-  return MarkStatus.Unmarked;
-}
-
 export type PrecinctScannerState =
   | 'connecting'
   | 'disconnected'
diff --git a/apps/scan/backend/src/util/option_mark_status.ts b/apps/scan/backend/src/util/option_mark_status.ts
index 2881ada91a..1ef3ac7319 100644
--- a/apps/scan/backend/src/util/option_mark_status.ts
+++ b/apps/scan/backend/src/util/option_mark_status.ts
@@ -6,7 +6,7 @@ import {
   MarkThresholds,
 } from '@votingworks/types';
 import { throwIllegalValue } from '@votingworks/basics';
-import { getMarkStatus } from '../types';
+import { getMarkStatus } from '@votingworks/utils';
 
 /**
  * state of the mark for a given contest and option
@@ -30,13 +30,13 @@ export function optionMarkStatus({
     switch (mark.type) {
       case 'candidate':
         if (mark.optionId === optionId) {
-          return getMarkStatus(mark, markThresholds);
+          return getMarkStatus(mark.score, markThresholds);
         }
         break;
 
       case 'yesno':
         if (mark.optionId === optionId) {
-          return getMarkStatus(mark, markThresholds);
+          return getMarkStatus(mark.score, markThresholds);
         }
         break;
 
diff --git a/apps/scan/backend/src/vx_interpreter.test.ts b/apps/scan/backend/src/vx_interpreter.test.ts
index ac0f469a5c..b997609f14 100644
--- a/apps/scan/backend/src/vx_interpreter.test.ts
+++ b/apps/scan/backend/src/vx_interpreter.test.ts
@@ -377,7 +377,7 @@ test('interprets marks in ballots', async () => {
           Object {
             "id": "write-in-0",
             "isWriteIn": true,
-            "name": "Write-In",
+            "name": "Write-In #1",
           },
         ],
       }
diff --git a/libs/backend/src/scan/cast_vote_records/build_cast_vote_record.ts b/libs/backend/src/scan/cast_vote_records/build_cast_vote_record.ts
index 6b2315a3f1..959a509b3e 100644
--- a/libs/backend/src/scan/cast_vote_records/build_cast_vote_record.ts
+++ b/libs/backend/src/scan/cast_vote_records/build_cast_vote_record.ts
@@ -16,12 +16,14 @@ import {
   getContests,
   InterpretedBmdPage,
   InterpretedHmpbPage,
+  MarkStatus,
   safeParseInt,
   SheetOf,
   VotesDict,
   YesNoContest,
   YesNoVote,
 } from '@votingworks/types';
+import { getMarkStatus } from '@votingworks/utils';
 
 import {
   BallotPageLayoutsLookup,
@@ -372,7 +374,9 @@ function buildOriginalSnapshot({
                 (Math.floor(mark.score * 100) / 100).toString(),
               ],
               HasIndication:
-                mark.score >= definiteMarkThreshold
+                getMarkStatus(mark.score, {
+                  definite: definiteMarkThreshold,
+                }) === MarkStatus.Marked
                   ? CVR.IndicationStatus.Yes
                   : CVR.IndicationStatus.No,
             },
diff --git a/libs/ballot-interpreter-nh/src/cli/interpret/index.ts b/libs/ballot-interpreter-nh/src/cli/interpret/index.ts
index d114648d73..61e6b4646a 100644
--- a/libs/ballot-interpreter-nh/src/cli/interpret/index.ts
+++ b/libs/ballot-interpreter-nh/src/cli/interpret/index.ts
@@ -1,4 +1,4 @@
-import { Result, ok, err, find, iter } from '@votingworks/basics';
+import { err, find, iter, ok, Result } from '@votingworks/basics';
 import { writeImageData } from '@votingworks/image-utils';
 import {
   MarkThresholds,
diff --git a/libs/ballot-interpreter-nh/src/interpret/convert_marks_to_adjudication_info.ts b/libs/ballot-interpreter-nh/src/interpret/convert_marks_to_adjudication_info.ts
index 3141567211..16e56085d8 100644
--- a/libs/ballot-interpreter-nh/src/interpret/convert_marks_to_adjudication_info.ts
+++ b/libs/ballot-interpreter-nh/src/interpret/convert_marks_to_adjudication_info.ts
@@ -7,7 +7,7 @@ import {
   MarkStatus,
   MarkThresholds,
 } from '@votingworks/types';
-import { ballotAdjudicationReasons } from '@votingworks/utils';
+import { ballotAdjudicationReasons, getMarkStatus } from '@votingworks/utils';
 import { InterpretedOvalMark } from '../types';
 
 /**
@@ -56,12 +56,14 @@ export function convertMarksToAdjudicationInfo({
         let fallbackStatus = MarkStatus.Unmarked;
 
         for (const mark of marks) {
-          if (mark.score >= markThresholds.definite) {
-            return MarkStatus.Marked;
+          const markStatus = getMarkStatus(mark.score, markThresholds);
+
+          if (markStatus === MarkStatus.Marked) {
+            return markStatus;
           }
 
-          if (mark.score >= markThresholds.marginal) {
-            fallbackStatus = MarkStatus.Marginal;
+          if (markStatus === MarkStatus.Marginal) {
+            fallbackStatus = markStatus;
           }
         }
 
diff --git a/libs/ballot-interpreter-nh/src/interpret/convert_marks_to_votes.ts b/libs/ballot-interpreter-nh/src/interpret/convert_marks_to_votes.ts
index 3b5c64fe4e..1ba1a61d49 100644
--- a/libs/ballot-interpreter-nh/src/interpret/convert_marks_to_votes.ts
+++ b/libs/ballot-interpreter-nh/src/interpret/convert_marks_to_votes.ts
@@ -1,16 +1,58 @@
+import { assert, find, iter, throwIllegalValue } from '@votingworks/basics';
 import {
-  Candidate,
-  ContestOptionId,
+  BallotTargetMark,
   Contests,
   MarkThresholds,
-  Vote,
   VotesDict,
 } from '@votingworks/types';
-import { assert, find, throwIllegalValue } from '@votingworks/basics';
-import makeDebug from 'debug';
+import { convertMarksToVotesDict } from '@votingworks/utils';
 import { InterpretedOvalMark } from '../types';
 
-const log = makeDebug('ballot-interpreter-nh:interpret');
+function convertNewHampshireMarkToSharedMark(
+  contests: Contests,
+  mark: InterpretedOvalMark
+): BallotTargetMark {
+  const contest = find(contests, (c) => c.id === mark.gridPosition.contestId);
+  if (contest.type === 'candidate') {
+    return {
+      type: 'candidate',
+      contestId: contest.id,
+      optionId:
+        mark.gridPosition.type === 'option'
+          ? mark.gridPosition.optionId
+          : `write-in-${mark.gridPosition.writeInIndex}`,
+      score: mark.score,
+      bounds: mark.bounds,
+      scoredOffset: mark.scoredOffset,
+      target: {
+        inner: mark.bounds,
+        bounds: mark.bounds,
+      },
+    };
+  }
+
+  if (contest.type === 'yesno') {
+    assert(mark.gridPosition.type === 'option');
+    assert(
+      mark.gridPosition.optionId === 'yes' ||
+        mark.gridPosition.optionId === 'no'
+    );
+    return {
+      type: 'yesno',
+      contestId: contest.id,
+      optionId: mark.gridPosition.optionId,
+      score: mark.score,
+      bounds: mark.bounds,
+      scoredOffset: mark.scoredOffset,
+      target: {
+        inner: mark.bounds,
+        bounds: mark.bounds,
+      },
+    };
+  }
+
+  throwIllegalValue(contest, 'type');
+}
 
 /**
  * Convert a series of oval marks into a list of candidate votes.
@@ -18,74 +60,11 @@ const log = makeDebug('ballot-interpreter-nh:interpret');
 export function convertMarksToVotes(
   contests: Contests,
   markThresholds: MarkThresholds,
-  ovalMarks: readonly InterpretedOvalMark[]
+  ovalMarks: Iterable<InterpretedOvalMark>
 ): VotesDict {
-  const votes: VotesDict = {};
-
-  for (const mark of ovalMarks) {
-    const { gridPosition } = mark;
-    const { contestId } = gridPosition;
-    const contest = find(contests, (c) => c.id === contestId);
-
-    let vote: Vote;
-    let optionId: ContestOptionId;
-
-    if (contest.type === 'candidate') {
-      const candidate: Candidate =
-        gridPosition.type === 'option'
-          ? find(contest.candidates, (c) => c.id === gridPosition.optionId)
-          : {
-              id: `write-in-${gridPosition.writeInIndex}`,
-              name: `Write-In #${gridPosition.writeInIndex + 1}`,
-              isWriteIn: true,
-            };
-      vote = [candidate];
-      optionId = candidate.id;
-    } else if (contest.type === 'yesno') {
-      assert(gridPosition.type === 'option');
-      vote = [gridPosition.optionId] as Vote;
-      optionId = gridPosition.optionId;
-    } else {
-      throwIllegalValue(contest, 'type');
-    }
-
-    if (mark.score < markThresholds.marginal) {
-      log(
-        `Mark for contest '%s' option '%s' will be ignored, score is too low: %d < %d (marginal threshold)`,
-        contestId,
-        optionId,
-        mark.score,
-        markThresholds.marginal
-      );
-      continue;
-    }
-
-    if (mark.score < markThresholds.definite) {
-      log(
-        `Mark for contest '%s' option '%s' is marginal, score is too low: %d < %d (definite threshold)`,
-        contestId,
-        optionId,
-        mark.score,
-        markThresholds.definite
-      );
-      continue;
-    }
-
-    log(
-      `Mark for contest '%s' option '%s' will be counted, score is high enough: %d (definite threshold) ≤ %d`,
-      contestId,
-      optionId,
-      markThresholds.definite,
-      mark.score
-    );
-
-    if (!votes[contestId]) {
-      votes[contestId] = vote;
-    } else {
-      const existing = votes[contestId] as Vote;
-      votes[contestId] = [...existing, ...vote] as Vote;
-    }
-  }
-
-  return votes;
+  return convertMarksToVotesDict(
+    contests,
+    markThresholds,
+    iter(ovalMarks).map((m) => convertNewHampshireMarkToSharedMark(contests, m))
+  );
 }
diff --git a/libs/ballot-interpreter-vx/src/cli/commands/interpret.test.ts b/libs/ballot-interpreter-vx/src/cli/commands/interpret.test.ts
index 0687d8a911..6bfa664495 100644
--- a/libs/ballot-interpreter-vx/src/cli/commands/interpret.test.ts
+++ b/libs/ballot-interpreter-vx/src/cli/commands/interpret.test.ts
@@ -429,7 +429,7 @@ test('run interpret', async () => {
     ╟───────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────╢
     ║ Judge, Texas Supreme Court, Place 6                   │ Jane Bland                                                                                         │                                                                                                    ║
     ╟───────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────╢
-    ║ Member, Texas House of Representatives, District 111  │ Write-In                                                                                           │                                                                                                    ║
+    ║ Member, Texas House of Representatives, District 111  │ Write-In #1                                                                                        │                                                                                                    ║
     ╟───────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────╢
     ║ Dallas County Tax Assessor-Collector                  │ John Ames                                                                                          │                                                                                                    ║
     ╟───────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────╢
@@ -441,7 +441,7 @@ test('run interpret', async () => {
     ╟───────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────╢
     ║ Proposition R: Countywide Recycling Program           │                                                                                                    │ no                                                                                                 ║
     ╟───────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────╢
-    ║ City Council                                          │                                                                                                    │ Randall Rupp, Donald Davis, Write-In                                                               ║
+    ║ City Council                                          │                                                                                                    │ Randall Rupp, Donald Davis, Write-In #2                                                            ║
     ╟───────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────┼────────────────────────────────────────────────────────────────────────────────────────────────────╢
     ║ Mayor                                                 │                                                                                                    │                                                                                                    ║
     ╚═══════════════════════════════════════════════════════╧════════════════════════════════════════════════════════════════════════════════════════════════════╧════════════════════════════════════════════════════════════════════════════════════════════════════╝
@@ -764,7 +764,7 @@ test('run interpret with JSON output', async () => {
               Object {
                 "id": "write-in-0",
                 "isWriteIn": true,
-                "name": "Write-In",
+                "name": "Write-In #1",
               },
             ],
             "texas-sc-judge-place-6": Array [
diff --git a/libs/ballot-interpreter-vx/src/get_votes_from_marks.ts b/libs/ballot-interpreter-vx/src/get_votes_from_marks.ts
index 57e9f4884e..19cc471cb8 100644
--- a/libs/ballot-interpreter-vx/src/get_votes_from_marks.ts
+++ b/libs/ballot-interpreter-vx/src/get_votes_from_marks.ts
@@ -1,16 +1,5 @@
-import {
-  BallotMark,
-  CandidateContest,
-  Election,
-  unsafeParse,
-  VotesDict,
-  WriteInCandidateSchema,
-} from '@votingworks/types';
-import { find, throwIllegalValue } from '@votingworks/basics';
-import makeDebug from 'debug';
-import { addVote } from './hmpb/votes';
-
-const debug = makeDebug('ballot-interpreter-vx:getVotesFromMarks');
+import { BallotMark, Election, VotesDict } from '@votingworks/types';
+import { convertMarksToVotesDict } from '@votingworks/utils';
 
 /**
  * Gets the votes where the given marks have a high enough score to count, where
@@ -22,63 +11,9 @@ export function getVotesFromMarks(
   marks: readonly BallotMark[],
   { markScoreVoteThreshold }: { markScoreVoteThreshold: number }
 ): VotesDict {
-  const votes: VotesDict = {};
-
-  for (const mark of marks) {
-    switch (mark.type) {
-      case 'candidate':
-        if (mark.score >= markScoreVoteThreshold) {
-          debug(
-            `'%s' contest '%s' mark score (%d) for '%s' meets vote threshold (%d)`,
-            mark.type,
-            mark.contestId,
-            mark.score,
-            mark.optionId,
-            markScoreVoteThreshold
-          );
-          const contest = find(
-            election.contests,
-            (c): c is CandidateContest => c.id === mark.contestId
-          );
-          const option = contest.candidates.find((c) => c.id === mark.optionId);
-          if (!option || option.isWriteIn) {
-            addVote(
-              election,
-              votes,
-              mark.contestId,
-              unsafeParse(
-                WriteInCandidateSchema,
-                option ?? {
-                  id: mark.optionId,
-                  name: 'Write-In',
-                  isWriteIn: true,
-                }
-              )
-            );
-          } else {
-            addVote(election, votes, mark.contestId, mark.optionId);
-          }
-        }
-        break;
-
-      case 'yesno':
-        if (mark.score >= markScoreVoteThreshold) {
-          debug(
-            `'%s' contest '%s' mark score (%d) for '%s' meets vote threshold (%d)`,
-            mark.type,
-            mark.contestId,
-            mark.score,
-            mark.optionId,
-            markScoreVoteThreshold
-          );
-          addVote(election, votes, mark.contestId, mark.optionId);
-        }
-        break;
-
-      default:
-        throwIllegalValue(mark, 'type');
-    }
-  }
-
-  return votes;
+  return convertMarksToVotesDict(
+    election.contests,
+    { definite: markScoreVoteThreshold },
+    marks
+  );
 }
diff --git a/libs/ballot-interpreter-vx/src/interpreter/interpret_votes.test.ts b/libs/ballot-interpreter-vx/src/interpreter/interpret_votes.test.ts
index df2feefc6a..5d866f672b 100644
--- a/libs/ballot-interpreter-vx/src/interpreter/interpret_votes.test.ts
+++ b/libs/ballot-interpreter-vx/src/interpreter/interpret_votes.test.ts
@@ -37,7 +37,7 @@ test('interpret votes', async () => {
         Object {
           "id": "write-in-0",
           "isWriteIn": true,
-          "name": "Write-In",
+          "name": "Write-In #1",
         },
       ],
       "texas-sc-judge-place-6": Array [
diff --git a/libs/ballot-interpreter-vx/src/interpreter/invalid_marks.test.ts b/libs/ballot-interpreter-vx/src/interpreter/invalid_marks.test.ts
index 816f2697a8..f07d5e47e9 100644
--- a/libs/ballot-interpreter-vx/src/interpreter/invalid_marks.test.ts
+++ b/libs/ballot-interpreter-vx/src/interpreter/invalid_marks.test.ts
@@ -43,7 +43,7 @@ test('invalid marks', async () => {
         Object {
           "id": "write-in-1",
           "isWriteIn": true,
-          "name": "Write-In",
+          "name": "Write-In #2",
         },
       ],
       "dallas-county-commissioners-court-pct-3": Array [
diff --git a/libs/ballot-interpreter-vx/src/interpreter/regression_page_outline.test.ts b/libs/ballot-interpreter-vx/src/interpreter/regression_page_outline.test.ts
index 89d8003e91..263acfff4c 100644
--- a/libs/ballot-interpreter-vx/src/interpreter/regression_page_outline.test.ts
+++ b/libs/ballot-interpreter-vx/src/interpreter/regression_page_outline.test.ts
@@ -42,7 +42,7 @@ test('regression: page outline', async () => {
         Object {
           "id": "write-in-1",
           "isWriteIn": true,
-          "name": "Write-In",
+          "name": "Write-In #2",
         },
       ],
       "dallas-county-commissioners-court-pct-3": Array [
diff --git a/libs/ballot-interpreter-vx/src/interpreter/stretch.test.ts b/libs/ballot-interpreter-vx/src/interpreter/stretch.test.ts
index 6533212d6d..787dfa8d1e 100644
--- a/libs/ballot-interpreter-vx/src/interpreter/stretch.test.ts
+++ b/libs/ballot-interpreter-vx/src/interpreter/stretch.test.ts
@@ -55,7 +55,7 @@ test('stretched precinct scanner ballot', async () => {
         Object {
           "id": "write-in-0",
           "isWriteIn": true,
-          "name": "Write-In",
+          "name": "Write-In #1",
         },
       ],
     }
diff --git a/libs/ballot-interpreter-vx/src/interpreter/two_column_template.test.ts b/libs/ballot-interpreter-vx/src/interpreter/two_column_template.test.ts
index 1d3ccb35a0..ee06f23586 100644
--- a/libs/ballot-interpreter-vx/src/interpreter/two_column_template.test.ts
+++ b/libs/ballot-interpreter-vx/src/interpreter/two_column_template.test.ts
@@ -1450,7 +1450,7 @@ test('interpret two-column template', async () => {
           Object {
             "id": "write-in-0",
             "isWriteIn": true,
-            "name": "Write-In",
+            "name": "Write-In #1",
           },
         ],
       }
diff --git a/libs/ballot-interpreter-vx/src/interpreter/upside_down_ballot.test.ts b/libs/ballot-interpreter-vx/src/interpreter/upside_down_ballot.test.ts
index a381d6f02e..c7c56f833b 100644
--- a/libs/ballot-interpreter-vx/src/interpreter/upside_down_ballot.test.ts
+++ b/libs/ballot-interpreter-vx/src/interpreter/upside_down_ballot.test.ts
@@ -46,7 +46,7 @@ test('upside-down ballot', async () => {
         Object {
           "id": "write-in-0",
           "isWriteIn": true,
-          "name": "Write-In",
+          "name": "Write-In #1",
         },
       ],
       "texas-sc-judge-place-6": Array [
diff --git a/libs/utils/src/votes.test.ts b/libs/utils/src/votes.test.ts
index ea70c02256..71b9b3d308 100644
--- a/libs/utils/src/votes.test.ts
+++ b/libs/utils/src/votes.test.ts
@@ -1,4 +1,6 @@
 import {
+  electionFamousNames2021Fixtures,
+  electionGridLayoutNewHampshireAmherstFixtures,
   electionMultiPartyPrimaryFixtures,
   electionPrimaryNonpartisanContestsFixtures,
   electionSample,
@@ -8,6 +10,7 @@ import {
 } from '@votingworks/fixtures';
 import {
   BallotIdSchema,
+  BallotTargetMark,
   CandidateContest,
   CastVoteRecord,
   Election,
@@ -20,10 +23,11 @@ import {
   TallyCategory,
   unsafeParse,
   VotingMethod,
+  WriteInCandidate,
   writeInCandidate,
   YesNoContest,
 } from '@votingworks/types';
-import { assert, find } from '@votingworks/basics';
+import { assert, find, typedAs } from '@votingworks/basics';
 import {
   ALL_PARTY_FILTER,
   buildVoteFromCvr,
@@ -38,6 +42,7 @@ import {
   getEmptyTally,
   getPartyIdForCvr,
   getSingleYesNoVote,
+  convertMarksToVotesDict,
   NONPARTISAN_FILTER,
   normalizeWriteInId,
   tallyVotesByContest,
@@ -1266,3 +1271,159 @@ test('castVoteRecordHasWriteIns with write-in votes', () => {
     })
   ).toEqual(true);
 });
+
+const ballotTargetMarkBase: Pick<
+  BallotTargetMark,
+  'bounds' | 'scoredOffset' | 'target'
+> = {
+  bounds: { x: 0, y: 0, width: 0, height: 0 },
+  scoredOffset: { x: 0, y: 0 },
+  target: {
+    inner: { x: 0, y: 0, width: 0, height: 0 },
+    bounds: { x: 0, y: 0, width: 0, height: 0 },
+  },
+};
+
+test('markInfoToVotesDict candidate', () => {
+  const { election } = electionFamousNames2021Fixtures;
+  const sherlockForMayorMark: BallotTargetMark = {
+    type: 'candidate',
+    contestId: 'mayor',
+    optionId: 'sherlock-holmes',
+    score: 0.5,
+    ...ballotTargetMarkBase,
+  };
+  const edisonForMayorMark: BallotTargetMark = {
+    type: 'candidate',
+    contestId: 'mayor',
+    optionId: 'thomas-edison',
+    score: 0.5,
+    ...ballotTargetMarkBase,
+  };
+  const writeInCandidateForMayorMark: BallotTargetMark = {
+    type: 'candidate',
+    contestId: 'mayor',
+    optionId: 'write-in',
+    score: 0.5,
+    ...ballotTargetMarkBase,
+  };
+  const indexedWriteInCandidateForMayorMark: BallotTargetMark = {
+    ...writeInCandidateForMayorMark,
+    optionId: 'write-in-0',
+  };
+  const mayorContest = find(
+    election.contests,
+    (c): c is CandidateContest =>
+      c.id === sherlockForMayorMark.contestId && c.type === 'candidate'
+  );
+  const sherlockCandidate = find(
+    mayorContest.candidates,
+    (c) => c.id === sherlockForMayorMark.optionId
+  );
+  const edisonCandidate = find(
+    mayorContest.candidates,
+    (c) => c.id === edisonForMayorMark.optionId
+  );
+  expect(
+    convertMarksToVotesDict(
+      election.contests,
+      { marginal: 0.04, definite: 0.1 },
+      [sherlockForMayorMark]
+    )
+  ).toEqual({ [mayorContest.id]: [sherlockCandidate] });
+  expect(
+    convertMarksToVotesDict(
+      election.contests,
+      { marginal: 0.5, definite: 0.8 },
+      [sherlockForMayorMark]
+    )
+  ).toEqual({});
+  expect(
+    convertMarksToVotesDict(
+      election.contests,
+      { marginal: 0.04, definite: 0.1 },
+      [sherlockForMayorMark, edisonForMayorMark]
+    )
+  ).toEqual({
+    [mayorContest.id]: [sherlockCandidate, edisonCandidate],
+  });
+  expect(
+    convertMarksToVotesDict(
+      election.contests,
+      { marginal: 0.04, definite: 0.1 },
+      [writeInCandidateForMayorMark]
+    )
+  ).toEqual({
+    [mayorContest.id]: [writeInCandidate],
+  });
+  expect(
+    convertMarksToVotesDict(
+      election.contests,
+      { marginal: 0.04, definite: 0.1 },
+      [indexedWriteInCandidateForMayorMark]
+    )
+  ).toEqual({
+    [mayorContest.id]: [
+      typedAs<WriteInCandidate>({
+        id: 'write-in-0',
+        name: 'Write-In #1',
+        isWriteIn: true,
+      }),
+    ],
+  });
+});
+
+test('markInfoToVotesDict yesno', () => {
+  const { election } = electionGridLayoutNewHampshireAmherstFixtures;
+  const yesnoContest = find(
+    election.contests,
+    (c): c is YesNoContest => c.type === 'yesno'
+  );
+  const yesMark: BallotTargetMark = {
+    type: 'yesno',
+    contestId: yesnoContest.id,
+    optionId: 'yes',
+    score: 0.5,
+    bounds: { x: 0, y: 0, width: 0, height: 0 },
+    scoredOffset: { x: 0, y: 0 },
+    target: {
+      inner: { x: 0, y: 0, width: 0, height: 0 },
+      bounds: { x: 0, y: 0, width: 0, height: 0 },
+    },
+  };
+  const noMark: BallotTargetMark = {
+    type: 'yesno',
+    contestId: yesnoContest.id,
+    optionId: 'no',
+    score: 0.5,
+    bounds: { x: 0, y: 0, width: 0, height: 0 },
+    scoredOffset: { x: 0, y: 0 },
+    target: {
+      inner: { x: 0, y: 0, width: 0, height: 0 },
+      bounds: { x: 0, y: 0, width: 0, height: 0 },
+    },
+  };
+  expect(
+    convertMarksToVotesDict(
+      election.contests,
+      { marginal: 0.04, definite: 0.1 },
+      [yesMark]
+    )
+  ).toEqual({ [yesnoContest.id]: ['yes'] });
+  expect(
+    convertMarksToVotesDict(
+      election.contests,
+      { marginal: 0.5, definite: 0.8 },
+      [yesMark]
+    )
+  ).toEqual({});
+  expect(
+    convertMarksToVotesDict(
+      election.contests,
+      { marginal: 0.04, definite: 0.1 },
+      [yesMark, noMark]
+    )
+  ).toEqual({
+    [yesnoContest.id]: ['yes', 'no'],
+  });
+});
diff --git a/libs/utils/src/votes.ts b/libs/utils/src/votes.ts
index 924016464c..eb4d9fb7c1 100644
--- a/libs/utils/src/votes.ts
+++ b/libs/utils/src/votes.ts
@@ -1,4 +1,6 @@
+import { assert, find, throwIllegalValue, typedAs } from '@votingworks/basics';
 import {
+  BallotTargetMark,
   BatchTally,
   Candidate,
   CandidateContest,
@@ -8,26 +10,32 @@ import {
   ContestId,
   ContestOptionId,
   ContestOptionTally,
+  Contests,
   ContestTally,
   ContestTallyMeta,
   Dictionary,
   Election,
   FullElectionTally,
   getBallotStyle,
+  MarkStatus,
+  MarkThresholds,
   Optional,
   PartyId,
   PrecinctId,
+  safeParse,
+  safeParseInt,
   Tally,
   TallyCategory,
+  Vote,
   VotesDict,
   VotingMethod,
   writeInCandidate,
+  WriteInIdSchema,
   YesNoContest,
   YesNoVote,
   YesNoVoteId,
   YesOrNo,
 } from '@votingworks/types';
-import { assert, throwIllegalValue, find, typedAs } from '@votingworks/basics';
 
 const MISSING_BATCH_ID = 'missing-batch-id';
 
@@ -653,3 +661,104 @@ export function castVoteRecordHasWriteIns(cvr: CastVoteRecord): boolean {
   }
   return false;
 }
+
+type MarkThresholdsOptionalMarginal = Omit<MarkThresholds, 'marginal'> &
+  Partial<Pick<MarkThresholds, 'marginal'>>;
+
+export function getMarkStatus(
+  markScore: BallotTargetMark['score'],
+  markThresholds: MarkThresholds
+): MarkStatus;
+export function getMarkStatus(
+  markScore: BallotTargetMark['score'],
+  markThresholds: Omit<MarkThresholds, 'marginal'>
+): Exclude<MarkStatus, MarkStatus.Marginal>;
+export function getMarkStatus(
+  markScore: BallotTargetMark['score'],
+  markThresholds: MarkThresholdsOptionalMarginal
+): MarkStatus {
+  if (markScore >= markThresholds.definite) {
+    return MarkStatus.Marked;
+  }
+
+  if (
+    typeof markThresholds.marginal === 'number' &&
+    markScore >= markThresholds.marginal
+  ) {
+    return MarkStatus.Marginal;
+  }
+
+  return MarkStatus.Unmarked;
+}
+
+function markToCandidateVotes(
+  contest: CandidateContest,
+  markThresholds: Pick<MarkThresholds, 'definite'>,
+  mark: BallotTargetMark
+): CandidateVote {
+  assert(mark.type === 'candidate');
+  if (getMarkStatus(mark.score, markThresholds) !== MarkStatus.Marked) {
+    return [];
+  }
+
+  if (safeParse(WriteInIdSchema, mark.optionId).isOk()) {
+    const indexedWriteInMatch = mark.optionId.match(/^write-in-(\d+)$/);
+
+    if (!indexedWriteInMatch) {
+      return [writeInCandidate];
+    }
+
+    const writeInIndex = safeParseInt(indexedWriteInMatch[1]).assertOk(
+      '\\d+ ensures this is an integer'
+    );
+
+    return [
+      {
+        id: mark.optionId,
+        name: `Write-In #${writeInIndex + 1}`,
+        isWriteIn: true,
+      },
+    ];
+  }
+
+  const candidate = contest.candidates.find((c) => c.id === mark.optionId);
+  assert(candidate, `Candidate not found: ${mark.contestId}/${mark.optionId}`);
+  return [candidate];
+}
+
+function markToYesNoVotes(
+  markThresholds: Pick<MarkThresholds, 'definite'>,
+  mark: BallotTargetMark
+): YesNoVote {
+  assert(mark.type === 'yesno');
+  return getMarkStatus(mark.score, markThresholds) === MarkStatus.Marked
+    ? [mark.optionId]
+    : [];
+}
+
+/**
+ * Convert {@link BallotTargetMark}s to {@link VotesDict}.
+ */
+export function convertMarksToVotesDict(
+  contests: Contests,
+  markThresholds: MarkThresholdsOptionalMarginal,
+  marks: Iterable<BallotTargetMark>
+): VotesDict {
+  const votesDict: VotesDict = {};
+  for (const mark of marks) {
+    const contest = contests.find((c) => c.id === mark.contestId);
+    assert(contest, `Contest not found: ${mark.contestId}`);
+    const existingVotes = votesDict[mark.contestId] ?? [];
+    const newVotes =
+      contest.type === 'candidate'
+        ? markToCandidateVotes(contest, markThresholds, mark)
+        : contest.type === 'yesno'
+        ? markToYesNoVotes(markThresholds, mark)
+        : /* istanbul ignore next */ throwIllegalValue(contest, 'type');
+
+    if (newVotes.length > 0) {
+      votesDict[mark.contestId] = [...existingVotes, ...newVotes] as Vote;
+    }
+  }
+  return votesDict;
+}