- Lead
- 11,875
- Total
- 17,468
- vs nation
- D+69.5
Massachusetts 131st State House District
President margin by year
Place winner margin
President results by year
Modeled candidate-vote estimate on current district boundaries
- Lead
- 15,209
- Total
- 19,477
- vs nation
- D+73.6
- Lead
- 14,468
- Total
- 18,794
- vs nation
- D+74.9
- Lead
- 12,456
- Total
- 16,455
- vs nation
- D+71.8
- Lead
- 11,735
- Total
- 15,597
- vs nation
- D+68.0
- Lead
- 10,194
- Total
- 13,835
- vs nation
- D+76.1
- Lead
- 8,721
- Total
- 12,490
- vs nation
- D+69.3
- Lead
- 8,252
- Total
- 11,529
- vs nation
- D+63.1
Key facts
- 2024 presidential margin
- D+68.0MIT Election Lab
- Population
- 41,8202024 5-year
- Population density
- 20,910 / sq mi2024 5-year · TIGER/Line
- Land area
- 2 sq miTIGER/Line
- Median household income
- $84,9872024 5-year
- White (non-Hispanic)
- 45.1%2024 5-year
- Black
- 18.5%2024 5-year
- Hispanic / Latino
- 19.4%2024 5-year
- Peak Democratic margin
- D+85.7 in 1964MIT Election Lab
- Most similar
- 15th Suffolk District, MA · twin score 97.7
presidential history
Party record book
Massachusetts 131st State House District · the strongest Democratic and Republican presidential performances recorded here, measured three ways.
1892–2024 (partial returns from 1876) · 38 presidential cycles · 38 with a vote-share denominator · 34 with a national benchmark
Highest vote share
Largest share of the presidential candidate vote cast here.
Democratic
Lyndon B. Johnson1964
92.7%
16,809 votes · D+85.7 · modeled estimate
Runner-up · Joe Biden, 2020 · 88.2%
Republican
William McKinley1896
42.3%
1,694 votes · D+4.1 · modeled estimate
Runner-up · Warren G. Harding, 1920 · 40.6%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Harry S. Truman1948
17,354votes
80.9% of the vote · D+65.4 · modeled estimate
Runner-up · Joe Biden, 2020 · 17,177 votes
Republican
Dwight D. Eisenhower1956
5,158votes
29.0% of the vote · D+41.3 · modeled estimate
Runner-up · Dwight D. Eisenhower, 1952 · 5,118 votes
Best relative to the U.S.
This Place’s margin against the national margin in the same election — positive when it leaned toward the party more than the country did.
Democratic
George McGovern1972
+82.9pts D vs U.S.
Place D+59.8 · U.S. R+23.2 · modeled estimate
Runner-up · Al Smith, 1928 · +78.8 pts
Republican
William McKinley1896
−10.2pts R vs U.S.
Place D+4.1 · U.S. R+6.1 · modeled estimate
Runner-up · William H. Taft, 1912 · −23.2 pts
Current officeholders
State legislative officeholder from OpenStates nightly current-legislator data.
Senate and governor results are in the Office selector at the top of this page.
U.S. House
Each row is a county-allocated estimate of U.S. House votes for this district — county returns apportioned onto its boundary, not precinct-counted. “Vote lead” is the estimated local lead here, not necessarily the winner of the full contest.
| Year | Vote lead | Democratic | Republican | Total |
|---|---|---|---|---|
| 2024 | D | 92.7%12,538 | 7.3%982 | 13,520 |
| 2020 | D | 96.7%13,982 | 3.3%474 | 14,456 |
The 9th Suffolk District posts presidential margins rarely seen outside major urban cores — its D+68.0 result in 2024 reflects a densely populated Boston-area constituency where competitive general elections are essentially nonexistent.
Across the recorded series it reached a Democratic high of 85.7 points in 1964. Between 2020 and 2024 the district moved 10.1 points toward the Republican candidate; the 2024 margin was 68.0 points.
A population of 41,820, a 45% non-Hispanic-white share, and a median household income of $84,987 describe the district. The district's voting pattern over the last decade is most similar to that of 15th Suffolk District and 26th Middlesex District.
The state-house districts whose fingerprint — 2000–2024 trajectory, demographics, ancestry, religion — sits closest to this one, and why.
Twin score (0–100) = weighted cosine between tier-standardized fingerprints: presidential margins 2000–2024 with 12-yr trend and elasticity, ACS income, age, education, population and race, top reported ancestries, and religious adherence — chips name the closest-shared dimensions and the widest gap. Re-weight the groups in the twins explorer.
District research tools
Open the source-auditable district brief for electoral baseline, electorate, current-cycle coverage, geography, official dates, and methodology. Open campaign intelligence report → · Browse all comparisons →
Massachusetts 131st State House District. Akashic. https://akashic.app/sld-lower/25131/. Accessed May 20, 2026. License: CC BY 4.0.