- Lead
- 16,926
- Total
- 91,799
- vs nation
- D+19.9
Arizona 21st State Senate District
President margin by year
Place winner margin
President results by year
Modeled candidate-vote estimate on current district boundaries
- Lead
- 26,879
- Total
- 94,482
- vs nation
- D+24.0
- Lead
- 21,725
- Total
- 76,048
- vs nation
- D+26.5
- Lead
- 15,224
- Total
- 67,720
- vs nation
- D+18.6
- Lead
- 14,097
- Total
- 68,851
- vs nation
- D+13.2
- Lead
- 11,803
- Total
- 62,976
- vs nation
- D+21.2
- Lead
- 9,911
- Total
- 49,362
- vs nation
- D+19.6
- Lead
- 12,099
- Total
- 45,935
- vs nation
- D+17.8
Key facts
- 2024 presidential margin
- D+18.4MIT Election Lab
- Population
- 244,4122024 5-year
- Population density
- 116 / sq mi2024 5-year · TIGER/Line
- Land area
- 2,111 sq miTIGER/Line
- Median household income
- $59,2482024 5-year
- White (non-Hispanic)
- 30.6%2024 5-year
- Black
- 4.6%2024 5-year
- Hispanic / Latino
- 58.4%2024 5-year
- Peak Democratic margin
- D+53.3 in 1936MIT Election Lab
- Peak Republican margin
- R+9.2 in 1956MIT Election Lab
- Most similar
- State Senate District 24, AZ · twin score 97.1
presidential history
Party record book
Arizona 21st State Senate District · the strongest Democratic and Republican presidential performances recorded here, measured three ways.
1912–2024 · 29 presidential cycles
Highest vote share
Largest share of the presidential candidate vote cast here.
Democratic
Franklin D. Roosevelt1936
75.7%
4,448 votes · D+53.3 · modeled estimate
Runner-up · Franklin D. Roosevelt, 1932 · 74.2%
Republican
Dwight D. Eisenhower1956
54.6%
6,266 votes · R+9.2 · modeled estimate
Runner-up · Ronald Reagan, 1984 · 51.6%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Joe Biden2020
59,894votes
63.4% of the vote · D+28.4 · modeled estimate
Runner-up · Kamala Harris, 2024 · 53,605 votes
Republican
Donald Trump2024
36,679votes
40.0% of the vote · D+18.4 · modeled estimate
Runner-up · Donald Trump, 2020 · 33,015 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
John W. Davis1924
+40.5pts D vs U.S.
Place D+15.4 · U.S. R+25.2 · modeled estimate
Runner-up · James M. Cox, 1920 · +36.1 pts
Republican
Barry Goldwater1964
+1.8pts R vs U.S.
Place D+20.8 · U.S. D+22.6 · modeled estimate
Runner-up · Richard Nixon, 1968 · −4.0 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 | 62.3%34,252 | 37.7%20,722 | 54,974 |
Anchored in the fast-growing exurban and rural corridors south and east of the Phoenix metro, this district has posted Republican presidential margins exceeding 20 points in recent cycles, making it a structural safe seat in state legislative maps.
Across the recorded series it reached a Democratic high of 53.3 points in 1936 and a Republican high of 9.2 points in 1956. Between 2020 and 2024 the district moved 10.0 points toward the Republican candidate; the 2024 margin was 18.4 points.
A population of 244,412, a 31% non-Hispanic-white share, and a median household income of $59,248 describe the district. The district's voting pattern over the last decade is most similar to that of State Senate District 24 and State Senate District 22.
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 →
Arizona 21st State Senate District. Akashic. https://akashic.app/sld-upper/04021/. Accessed May 20, 2026. License: CC BY 4.0.