91755 leans Democratic by roughly 18 points: about 59% of voters vote Democratic and 41% Republican.
About 44% of adults in 91755 typically vote, below the U.S. average of about 62%. Among adults in 91755, ~26% vote Democratic, ~18% Republican, and ~56% don't vote. The map below shows estimated turnout by block group.
How 91755 compares
Among zip codes within 15 miles, 91755 leans more Democratic than 30 of 143 neighbors.
Politically, 91755 sits close to the rest of California.
Politics vary noticeably by block within 91755. The south side is the most Democratic-leaning (D+27) and the northwest side is the least Democratic-leaning (D+10), a spread of about 17 points.
Why 91755 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 91755, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 99% of residents in 91755 live in densely developed areas, about 62 points above the U.S. average of 36%.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; 91755, 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 91755 looks the way it does
Renters vote less often than owners. About 51% of households in 91755 rent, about 26 points above the U.S. average of 25%. High food insecurity lines up with lower turnout, and about 24% of adults in 91755 report food insecurity, above 87% 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.