94040 leans heavily Democratic by roughly 44 points: about 72% of voters vote Democratic and 28% Republican.
About 61% of adults in 94040 typically vote, near the U.S. average of about 62%. Among adults in 94040, ~44% vote Democratic, ~17% Republican, and ~39% don't vote. The map below shows estimated turnout by block group.
How 94040 compares
Among zip codes within 15 miles, 94040 leans more Democratic than 40 of 61 neighbors.
94040 runs about 24 points more Democratic than California as a whole.
Politics vary noticeably by block within 94040. The north side is the most Democratic-leaning (D+51) and the southeast side is the least Democratic-leaning (D+38), a spread of about 13 points.
Why 94040 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 94040, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 78% of adults in 94040 hold a bachelor's degree, about 49 points above the U.S. average of 28%. Dense areas vote Democratic, and 94040 sits in the top fifth on density (more than 99%, above 98% of zip codes). A high never-married share predicts Democratic voting, and about 38% of adults in 94040 have never been married, above 85% of zip codes.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; 94040, CA sits in the top tenth nationally on this measure. Paved ground does not change how people vote; it mostly reflects how urban and built-up a place is.
Why turnout in 94040 looks the way it does
Renters vote less often than owners. About 57% of households in 94040 rent, about 32 points above the U.S. average of 25%. Strong routine healthcare access lines up with higher turnout, and 94040 sits in the top quarter on routine-care measures. Crowded housing lines up with lower turnout, and about 5% of homes in 94040 have more than one occupant per room, above 88% 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.