- Lead
- 90,095
- Total
- 248,430
- vs nation
- D+37.7
California 78th State House District
President margin by year
Place winner margin
President results by year
Modeled candidate-vote estimate on current district boundaries
- Lead
- 104,998
- Total
- 271,081
- vs nation
- D+34.3
- Lead
- 77,296
- Total
- 227,540
- vs nation
- D+31.9
- Lead
- 47,939
- Total
- 202,230
- vs nation
- D+19.9
- Lead
- 55,043
- Total
- 209,856
- vs nation
- D+19.0
- Lead
- 20,245
- Total
- 187,663
- vs nation
- D+13.2
- Lead
- 19,576
- Total
- 159,508
- vs nation
- D+11.8
- Lead
- 20,263
- Total
- 148,511
- vs nation
- D+5.1
Key facts
- 2024 presidential margin
- D+36.3MIT Election Lab
- Population
- 511,6912024 5-year
- Population density
- 4,127 / sq mi2024 5-year · TIGER/Line
- Land area
- 124 sq miTIGER/Line
- Median household income
- $108,1642024 5-year
- White (non-Hispanic)
- 49.5%2024 5-year
- Black
- 4.7%2024 5-year
- Hispanic / Latino
- 22.1%2024 5-year
- Peak Democratic margin
- D+46.2 in 1912MIT Election Lab
- Peak Republican margin
- R+32.7 in 1924MIT Election Lab
- Most similar
- Assembly District 6, CA · twin score 94.5
presidential history
Party record book
California 78th 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
Franklin D. Roosevelt1936
70.8%
12,652 votes · D+43.1 · modeled estimate
Runner-up · Joe Biden, 2020 · 68.2%
Republican
Herbert Hoover1928
57.3%
6,497 votes · R+16.5 · modeled estimate
Runner-up · Ronald Reagan, 1984 · 57.1%
Most votes
Largest number of votes cast for the party’s presidential nominee here.
Democratic
Joe Biden2020
184,808votes
68.2% of the vote · D+38.7 · modeled estimate
Runner-up · Kamala Harris, 2024 · 165,192 votes
Republican
George W. Bush2004
82,356votes
43.9% of the vote · D+10.8 · modeled estimate
Runner-up · Donald Trump, 2020 · 79,810 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
+37.7pts D vs U.S.
Place D+36.3 · U.S. R+1.5 · modeled estimate
Runner-up · Joe Biden, 2020 · +34.3 pts
Republican
Ronald Reagan1980
+9.7pts R vs U.S.
Place R+19.5 · U.S. R+9.7 · modeled estimate
Runner-up · Calvin Coolidge, 1924 · +7.6 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.
Centered in Los Angeles County, AD-78 backed the 2024 Democratic presidential nominee by 36 points, reflecting a densely urban electorate where competitive general elections are rare and primary dynamics tend to drive outcomes.
Across the recorded series it reached a Democratic high of 46.2 points in 1912 and a Republican high of 32.7 points in 1924. Between 2020 and 2024 the district moved 2.5 points toward the Republican candidate; the 2024 margin was 36.3 points.
A population of 511,691, a 50% non-Hispanic-white share, and a median household income of $108,164 describe the district. The district's voting pattern over the last decade is most similar to that of Assembly District 6 and Assembly District 77.
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 →
California 78th State House District. Akashic. https://akashic.app/sld-lower/06078/. Accessed May 20, 2026. License: CC BY 4.0.