- Lead
- 11,824
- Total
- 300,555
- vs nation
- D+5.4
California 45th Congressional District
President margin by year
Place winner margin
President results by year
Modeled candidate-vote estimate on current district boundaries
- Lead
- 35,241
- Total
- 335,946
- vs nation
- D+6.0
- Lead
- 53,815
- Total
- 255,891
- vs nation
- D+18.9
- Lead
- 18,601
- Total
- 238,103
- vs nation
- D+4.0
- Lead
- 25,695
- Total
- 246,306
- vs nation
- D+3.2
- Lead
- 15,602
- Total
- 226,484
- vs nation
- R+4.4
- Lead
- 4,200
- Total
- 204,052
- vs nation
- R+2.6
- Lead
- 2,721
- Total
- 181,397
- vs nation
- R+10.0
Key facts
- 2024 presidential margin
- D+3.9MIT Election Lab
- Population
- 757,1282024 5-year
- Population density
- 7,609 / sq mi2024 5-year · TIGER/Line
- Land area
- 99.5 sq miTIGER/Line
- Median household income
- $105,1242024 5-year
- White (non-Hispanic)
- 20.0%2024 5-year
- Black
- 2.5%2024 5-year
- Hispanic / Latino
- 34.6%2024 5-year
- Peak Democratic margin
- D+38.0 in 1912MIT Election Lab
- Peak Republican margin
- R+61.5 in 1924MIT Election Lab
- Most similar
- Congressional District 28, CA · twin score 82.8
presidential history
Party record book
California 45th Congressional 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
Franklin D. Roosevelt1936
61.3%
16,542 votes · D+23.7 · modeled estimate
Runner-up · Hillary Clinton, 2016 · 57.4%
Republican
Herbert Hoover1928
74.7%
13,907 votes · R+50.8 · modeled estimate
Runner-up · Warren G. Harding, 1920 · 73.6%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Joe Biden2020
182,428votes
54.3% of the vote · D+10.5 · modeled estimate
Runner-up · Kamala Harris, 2024 · 151,830 votes
Republican
Donald Trump2020
147,187votes
43.8% of the vote · D+10.5 · modeled estimate
Runner-up · Donald Trump, 2024 · 140,006 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
Hillary Clinton2016
+18.9pts D vs U.S.
Place D+21.0 · U.S. D+2.1 · modeled estimate
Runner-up · Woodrow Wilson, 1912 · +18.4 pts
Republican
Calvin Coolidge1924
+36.3pts R vs U.S.
Place R+61.5 · U.S. R+25.2 · modeled estimate
Runner-up · Herbert Hoover, 1928 · +33.4 pts
Current officeholders
Federal officeholders only. State and local officeholders are planned for the next data pass.
Senate and governor results are in the Office selector at the top of this page.
U.S. House
Each result reflects the U.S. House district as it was drawn for that election; redistricting has redrawn these lines over time, so they can differ from the current 120th-Congress district shown on the map above.
CA-45 covers parts of Orange County once considered reliably Republican turf; the 2024 presidential margin of D+3.9 reflects a suburban realignment driven by demographic change and growing shares of college-educated and Asian American voters.
Across the recorded series it reached a Democratic high of 38.0 points in 1912 and a Republican high of 61.5 points in 1924. Between 2020 and 2024 the district moved 6.6 points toward the Republican candidate; the 2024 margin was 3.9 points.
A population of 757,128, a 20% non-Hispanic-white share, and a median household income of $105,124 describe the district. The district's voting pattern over the last decade is most similar to that of Congressional District 28 and Congressional District 6.
The congressional 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 →
California 45th Congressional District. Akashic. https://akashic.app/cd/0645/. Accessed May 20, 2026. License: CC BY 4.0.