- Lead
- 31,905
- Total
- 133,611
- vs nation
- D+25.4
Arizona 18th State Senate District
President margin by year
Place winner margin
President results by year
Modeled candidate-vote estimate on current district boundaries
- Lead
- 33,184
- Total
- 138,681
- vs nation
- D+19.5
- Lead
- 19,161
- Total
- 116,659
- vs nation
- D+14.3
- Lead
- 10,468
- Total
- 105,859
- vs nation
- D+6.0
- Lead
- 9,760
- Total
- 109,049
- vs nation
- D+1.7
- Lead
- 9,158
- Total
- 101,437
- vs nation
- D+11.5
- Lead
- 8,753
- Total
- 79,462
- vs nation
- D+10.5
- Lead
- 11,473
- Total
- 73,022
- vs nation
- D+7.2
Key facts
- 2024 presidential margin
- D+23.9MIT Election Lab
- Population
- 243,4112024 5-year
- Population density
- 2,554 / sq mi2024 5-year · TIGER/Line
- Land area
- 95.3 sq miTIGER/Line
- Median household income
- $71,9062024 5-year
- White (non-Hispanic)
- 63.9%2024 5-year
- Black
- 3.8%2024 5-year
- Hispanic / Latino
- 22.3%2024 5-year
- Peak Democratic margin
- D+35.4 in 1936MIT Election Lab
- Peak Republican margin
- R+22.0 in 1956MIT Election Lab
- Most similar
- Legislative (Senate) District 40, WA · twin score 82.7
presidential history
Party record book
Arizona 18th 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
66.9%
3,590 votes · D+35.4 · modeled estimate
Runner-up · Franklin D. Roosevelt, 1932 · 63.4%
Republican
Dwight D. Eisenhower1956
60.9%
10,508 votes · R+22.0 · modeled estimate
Runner-up · Dwight D. Eisenhower, 1952 · 58.6%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Joe Biden2020
84,893votes
61.2% of the vote · D+23.9 · modeled estimate
Runner-up · Kamala Harris, 2024 · 81,578 votes
Republican
Donald Trump2020
51,709votes
37.3% of the vote · D+23.9 · modeled estimate
Runner-up · Donald Trump, 2024 · 49,673 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
+25.4pts D vs U.S.
Place D+23.9 · U.S. R+1.5 · modeled estimate
Runner-up · Joe Biden, 2020 · +19.5 pts
Republican
Barry Goldwater1964
+12.3pts R vs U.S.
Place D+10.2 · U.S. D+22.6 · modeled estimate
Runner-up · Charles E. Hughes, 1916 · +7.9 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 | 57.4%64,871 | 42.6%48,193 | 113,064 |
With a 2024 presidential margin of D+24, this Maricopa County district ranks among the state's most reliably blue constituencies, reflecting the dense urban and minority-majority neighborhoods that anchor its electorate.
Across the recorded series it reached a Democratic high of 35.4 points in 1936 and a Republican high of 22.0 points in 1956. The 2024 margin was 23.9 points.
A population of 243,411, a 64% non-Hispanic-white share, and a median household income of $71,906 describe the district. The district's voting pattern over the last decade is most similar to that of Legislative (Senate) District 40 and State Senate District 12.
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 18th State Senate District. Akashic. https://akashic.app/sld-upper/04018/. Accessed May 20, 2026. License: CC BY 4.0.