91765 leans slightly Democratic by roughly 12 points: about 56% of voters vote Democratic and 44% Republican.
About 60% of adults in 91765 typically vote, near the U.S. average of about 62%. Among adults in 91765, ~34% vote Democratic, ~26% Republican, and ~40% don't vote. The map below shows estimated turnout by block group.
How 91765 compares
Among zip codes within 15 miles, 91765 leans more Democratic than 33 of 67 neighbors.
91765 runs about 9 points more Republican than California as a whole.
Why 91765 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 91765, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 53% of adults in 91765 hold a bachelor's degree, about 25 points above the U.S. average of 28%. Dense areas vote Democratic, and 91765 sits in the top fifth on density (about 80%, above 83% of zip codes).
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; 91765, CA sits in the top quarter 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 91765 looks the way it does
Turnout in 91765 sits close to the national pattern. Routine healthcare access, homeownership, education, and food security all land near their national averages here. 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.