96140 leans heavily Democratic by roughly 36 points: about 68% of voters vote Democratic and 32% Republican.
About 70% of adults in 96140 typically vote, above the U.S. average of about 62%. Among adults in 96140, ~48% vote Democratic, ~22% Republican, and ~30% don't vote. The map below shows estimated turnout by block group.
How 96140 compares
Among zip codes within 15 miles, 96140 leans more Democratic than 11 of 13 neighbors.
96140 runs about 16 points more Democratic than California as a whole.
Politics vary noticeably by block within 96140. The northwest side is the most Democratic-leaning (D+39) and the northeast side is the least Democratic-leaning (D+29), a spread of about 10 points.
Why 96140 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 96140, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 66% of adults in 96140 hold a bachelor's degree, about 37 points above the U.S. average of 28%. A high never-married share predicts Democratic voting, and about 35% of adults in 96140 have never been married, above 79% of zip codes.
High-school completion, uninsured rate, and voter turnout
Places that combine high-school-completion-heavy adults and a low uninsured rate tend to turn out at a higher rate, as 96140, CA does.
Why turnout in 96140 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 96140 is in the top quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The dental-visit rate here is about 78%, about 18 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and more than 99% of adults in 96140 have completed high school, in the top fraction 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.