94304 leans heavily Democratic by roughly 48 points: about 74% of voters vote Democratic and 26% Republican.
About 54% of adults in 94304 typically vote, below the U.S. average of about 62%. Among adults in 94304, ~40% vote Democratic, ~14% Republican, and ~46% don't vote. The map below shows estimated turnout by block group.
How 94304 compares
Among zip codes within 15 miles, 94304 leans more Democratic than 30 of 49 neighbors.
94304 runs about 28 points more Democratic than California as a whole.
Politics vary noticeably by block within 94304. The northwest side is the most Democratic-leaning (D+55) and the southeast side is the least Democratic-leaning (D+27), a spread of about 28 points.
Why 94304 leans the way it does
This analysis examined 14,881 data points per zip code to find what predicts political lean and turnout. The items below are a few correlations that stood out for 94304, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 83% of adults in 94304 hold a bachelor's degree, about 54 points above the U.S. average of 28%. Dense areas vote Democratic, and 94304 sits in the top fifth on density (about 85%, above 85% of zip codes).
Population density and Democratic lean
Places with high population density tend to lean Democratic; 94304, CA sits in the top quarter nationally on this measure.
Why turnout in 94304 looks the way it does
Renters vote less often than owners. About 73% of households in 94304 rent, about 48 points above the U.S. average of 25%. Strong routine healthcare access lines up with higher turnout, and 94304 sits in the top quarter on routine-care measures. Crowded housing lines up with lower turnout, and about 6% of homes in 94304 have more than one occupant per room, above 91% of zip codes. Learn more about the findings and methodology on the political spectrum map.
Nearby Zip Codes
Zip Codes with Similar Populations
Sources and methodology
Precinct-level voting records used to fit the model come from California Secretary of State, Elections, distributed by the Voting and Election Science Team. Demographic inputs come from the U.S. Census Bureau (ACS 5-year estimates and the 2020 Decennial Census). Health and environmental inputs come from the CDC (PLACES and the Environmental Justice Index). Land cover comes from the USGS and EPA. Election-day and lead-up weather come from PRISM 4km daily grids and the NOAA Global Historical Climatology Network. Mail-voting and election-administration patterns come from the MIT Election Lab's Survey of the Performance of American Elections. Block-group crime detail comes from CrimeGrade. Internet data and modeling support provided by ISPreports.org.
Modeling and analysis by the BestNeighborhood data science team. Full methodology and findings: political spectrum map.
Methodology reviewed by the BestNeighborhood data team. Last updated May 2026.