- Lead
- 2,708
- Total
- 51,788
- vs nation
- D+6.7
Connecticut 18th State Senate District
President margin by year
Place winner margin
President results by year
Modeled candidate-vote estimate on current district boundaries
- Lead
- 4,407
- Total
- 52,166
- vs nation
- D+4.0
- Lead
- 83
- Total
- 45,662
- vs nation
- R+2.3
- Lead
- 5,464
- Total
- 42,016
- vs nation
- D+9.1
- Lead
- 7,035
- Total
- 45,628
- vs nation
- D+8.1
- Lead
- 3,382
- Total
- 43,320
- vs nation
- D+10.3
- Lead
- 5,346
- Total
- 39,747
- vs nation
- D+12.9
- Lead
- 6,349
- Total
- 37,755
- vs nation
- D+8.3
Key facts
- 2024 presidential margin
- D+5.2MIT Election Lab
- Population
- 99,2062024 5-year
- Population density
- 333 / sq mi2024 5-year · TIGER/Line
- Land area
- 298 sq miTIGER/Line
- Median household income
- $90,4702024 5-year
- White (non-Hispanic)
- 80.0%2024 5-year
- Black
- 3.0%2024 5-year
- Hispanic / Latino
- 7.3%2024 5-year
- Peak Democratic margin
- D+35.7 in 1964MIT Election Lab
- Peak Republican margin
- R+36.6 in 1924MIT Election Lab
- Most similar
- State Senate District 35, CT · twin score 95.4
presidential history
Party record book
Connecticut 18th State Senate 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
67.8%
19,512 votes · D+35.7 · modeled estimate
Runner-up · Barack Obama, 2008 · 57.0%
Republican
William McKinley1896
66.1%
4,116 votes · R+35.2 · modeled estimate
Runner-up · Warren G. Harding, 1920 · 65.6%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Joe Biden2020
27,714votes
53.1% of the vote · D+8.4 · modeled estimate
Runner-up · Kamala Harris, 2024 · 26,806 votes
Republican
Ronald Reagan1984
24,151votes
63.7% of the vote · R+27.9 · modeled estimate
Runner-up · Donald Trump, 2024 · 24,098 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
Lyndon B. Johnson1964
+13.1pts D vs U.S.
Place D+35.7 · U.S. D+22.6 · modeled estimate
Runner-up · Al Gore, 2000 · +12.9 pts
Republican
William McKinley1896
+29.1pts R vs U.S.
Place R+35.2 · U.S. R+6.1 · modeled estimate
Runner-up · Alf Landon, 1936 · +22.3 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 |
|---|---|---|---|---|
| 2020 | D | 61.4%26,148 | 38.6%16,455 | 42,603 |
| 2018 | D | 64.8%22,895 | 35.2%12,435 | 35,330 |
Connecticut 18th State Senate District sits in New England. In 2024 it voted Democratic.
Across the recorded series it reached a Democratic high of 35.7 points in 1964 and a Republican high of 36.6 points in 1924. Between 2020 and 2024 the district moved 3.2 points toward the Republican candidate; the 2024 margin was 5.2 points.
A population of 99,206, a 80% non-Hispanic-white share, and a median household income of $90,470 describe the district. The district's voting pattern over the last decade is most similar to that of State Senate District 35 and State Senate District 19.
The state-senate 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 →
Connecticut 18th State Senate District. Akashic. https://akashic.app/sld-upper/09018/. Accessed May 20, 2026. License: CC BY 4.0.