91746 leans Democratic by roughly 30 points: about 65% of voters vote Democratic and 35% Republican.
About 44% of adults in 91746 typically vote, below the U.S. average of about 62%. Among adults in 91746, ~29% vote Democratic, ~15% Republican, and ~56% don't vote. The map below shows estimated turnout by block group.
How 91746 compares
Among zip codes within 15 miles, 91746 leans more Democratic than 66 of 95 neighbors.
91746 runs about 10 points more Democratic than California as a whole.
Politics vary noticeably by block within 91746. The northeast side is the most Democratic-leaning (D+34) and the southwest side is the least Democratic-leaning (D+21), a spread of about 12 points.
Why 91746 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 91746, not a ranked or complete list of what matters most.
Dense areas vote Democratic. More than 99% of residents in 91746 live in densely developed areas, about 64 points above the U.S. average of 36%. A high never-married share predicts Democratic voting, and about 42% of adults in 91746 have never been married, above 89% of zip codes.
Population density and Democratic lean
Places with high population density tend to lean Democratic; 91746, CA sits in the top tenth nationally on this measure.
Why turnout in 91746 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 91746 is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. High food insecurity lines up with lower turnout, and about 27% of adults in 91746 report food insecurity, above 91% of zip codes. Low high-school completion lines up with lower turnout, and about 69% of adults in 91746 have completed high school, below 98% 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.