- Lead
- 15,332
- Total
- 131,539
- vs nation
- D+13.1
New Jersey 21st State House District
President margin by year
Place winner margin
President results by year
Modeled candidate-vote estimate on current district boundaries
- Lead
- 23,606
- Total
- 136,608
- vs nation
- D+12.8
- Lead
- 8,821
- Total
- 116,110
- vs nation
- D+5.5
- Lead
- 4,182
- Total
- 107,150
- vs nation
- Even
- Lead
- 1,048
- Total
- 114,565
- vs nation
- R+6.4
- Lead
- 9,761
- Total
- 107,835
- vs nation
- R+6.6
- Lead
- 3,754
- Total
- 95,211
- vs nation
- R+4.5
- Lead
- 2,041
- Total
- 94,357
- vs nation
- R+10.7
Key facts
- 2024 presidential margin
- D+11.7MIT Election Lab
- Population
- 229,2932024 5-year
- Population density
- 1,664 / sq mi2024 5-year · TIGER/Line
- Land area
- 138 sq miTIGER/Line
- Median household income
- $177,7042024 5-year
- White (non-Hispanic)
- 68.6%2024 5-year
- Black
- 3.1%2024 5-year
- Hispanic / Latino
- 11.3%2024 5-year
- Peak Democratic margin
- D+17.3 in 2020MIT Election Lab
- Peak Republican margin
- R+60.3 in 1920MIT Election Lab
- Most similar
- Assembly District 39, NJ · twin score 92.2
presidential history
Party record book
New Jersey 21st 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
Joe Biden2020
57.6%
78,662 votes · D+17.3 · modeled estimate
Runner-up · Lyndon B. Johnson, 1964 · 56.1%
Republican
Warren G. Harding1920
78.3%
17,845 votes · R+60.3 · modeled estimate
Runner-up · Dwight D. Eisenhower, 1956 · 76.0%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Joe Biden2020
78,662votes
57.6% of the vote · D+17.3 · modeled estimate
Runner-up · Kamala Harris, 2024 · 71,825 votes
Republican
Ronald Reagan1984
74,862votes
69.6% of the vote · R+40.3 · modeled estimate
Runner-up · Richard Nixon, 1972 · 74,618 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
Kamala Harris2024
+13.1pts D vs U.S.
Place D+11.7 · U.S. R+1.5 · modeled estimate
Runner-up · Joe Biden, 2020 · +12.8 pts
Republican
Herbert Hoover1932
+46.4pts R vs U.S.
Place R+28.6 · U.S. D+17.8 · modeled estimate
Runner-up · Dwight D. Eisenhower, 1956 · +37.5 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.
Assembly District 21 delivers presidential margins exceeding 30 points, reflecting a densely populated, majority-minority constituency that has shifted further left over successive election cycles.
Across the recorded series it reached a Democratic high of 17.3 points in 2020 and a Republican high of 60.3 points in 1920. Between 2020 and 2024 the district moved 5.6 points toward the Republican candidate; the 2024 margin was 11.7 points.
A population of 229,293, a 69% non-Hispanic-white share, and a median household income of $177,704 describe the district. The district's voting pattern over the last decade is most similar to that of Assembly District 39 and State House District 51.
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 →
New Jersey 21st State House District. Akashic. https://akashic.app/sld-lower/34021/. Accessed May 20, 2026. License: CC BY 4.0.