- Lead
- 84,888
- Total
- 302,300
- vs nation
- D+29.6
California 20th State Senate District
President margin by year
Place winner margin
President results by year
Modeled candidate-vote estimate on current district boundaries
- Lead
- 153,955
- Total
- 355,938
- vs nation
- D+38.8
- Lead
- 145,393
- Total
- 280,949
- vs nation
- D+49.7
- Lead
- 115,651
- Total
- 259,862
- vs nation
- D+40.6
- Lead
- 116,967
- Total
- 270,064
- vs nation
- D+36.0
- Lead
- 75,326
- Total
- 245,814
- vs nation
- D+33.1
- Lead
- 74,691
- Total
- 219,156
- vs nation
- D+33.6
- Lead
- 61,213
- Total
- 196,794
- vs nation
- D+22.6
Key facts
- 2024 presidential margin
- D+28.1MIT Election Lab
- Population
- 942,9062024 5-year
- Population density
- 4,247 / sq mi2024 5-year · TIGER/Line
- Land area
- 222 sq miTIGER/Line
- Median household income
- $79,4102024 5-year
- White (non-Hispanic)
- 23.9%2024 5-year
- Black
- 3.5%2024 5-year
- Hispanic / Latino
- 60.1%2024 5-year
- Peak Democratic margin
- D+51.8 in 2016MIT Election Lab
- Peak Republican margin
- R+56.0 in 1924MIT Election Lab
- Most similar
- State Senate District 33, CA · twin score 99.3
presidential history
Party record book
California 20th 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
Hillary Clinton2016
72.8%
204,652 votes · D+51.8 · modeled estimate
Runner-up · Barack Obama, 2012 · 70.9%
Republican
Herbert Hoover1928
67.6%
39,082 votes · R+37.4 · modeled estimate
Runner-up · Theodore Roosevelt, 1904 · 66.9%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Joe Biden2020
250,990votes
70.5% of the vote · D+43.3 · modeled estimate
Runner-up · Hillary Clinton, 2016 · 204,652 votes
Republican
Richard Nixon1972
119,246votes
52.7% of the vote · R+9.0 · modeled estimate
Runner-up · Ronald Reagan, 1984 · 109,602 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
+49.7pts D vs U.S.
Place D+51.8 · U.S. D+2.1 · modeled estimate
Runner-up · Barack Obama, 2012 · +40.6 pts
Republican
Calvin Coolidge1924
+30.9pts R vs U.S.
Place R+56.0 · U.S. R+25.2 · modeled estimate
Runner-up · Theodore Roosevelt, 1904 · +28.3 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.
California 20th State Senate District sits in the Pacific Coast. In 2024 it voted Democratic.
Across the recorded series it reached a Democratic high of 51.8 points in 2016 and a Republican high of 56.0 points in 1924. Between 2020 and 2024 the district moved 15.2 points toward the Republican candidate; the 2024 margin was 28.1 points.
A population of 942,906, a 24% non-Hispanic-white share, and a median household income of $79,410 describe the district. The district's voting pattern over the last decade is most similar to that of State Senate District 33 and State Senate District 18.
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 →
California 20th State Senate District. Akashic. https://akashic.app/sld-upper/06020/. Accessed May 20, 2026. License: CC BY 4.0.