91011 leans Democratic by roughly 20 points: about 60% of voters vote Democratic and 40% Republican.
About 79% of adults in 91011 typically vote, above the U.S. average of about 62%. Among adults in 91011, ~47% vote Democratic, ~32% Republican, and ~21% don't vote. The map below shows estimated turnout by block group.
How 91011 compares
Among zip codes within 15 miles, 91011 leans more Democratic than 25 of 107 neighbors.
Politically, 91011 sits close to the rest of California.
Politics vary noticeably by block within 91011. The west side is the most Democratic-leaning (D+24) and the northeast side is the least Democratic-leaning (D+13), a spread of about 12 points.
Why 91011 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 91011, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 76% of adults in 91011 hold a bachelor's degree, about 47 points above the U.S. average of 28%. Dense areas vote Democratic, and 91011 sits in the top fifth on density (about 87%, above 86% of zip codes).
Preventive-care access and voter turnout
Places with strong routine preventive-care access tend to turn out at a higher rate; 91011, CA sits in the top tenth nationally on this measure. Dental visits do not drive turnout; the rate reflects income, insurance, and healthcare access, which line up with who votes.
Why turnout in 91011 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 91011 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 77%, about 17 points above the U.S. average of 60%. Homeowners vote more often than renters, and about 88% of households in 91011 own their home, compared to around 55% in nearby zip codes. High high-school completion lines up with higher turnout, and about 98% of adults in 91011 have completed high school, above 93% 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.