93621 leans heavily Republican by roughly 46 points: about 27% of voters vote Democratic and 73% Republican.
About 56% of adults in 93621 typically vote, below the U.S. average of about 62%. Among adults in 93621, ~15% vote Democratic, ~41% Republican, and ~44% don't vote. The map below shows estimated turnout by block group.
How 93621 compares
Among zip codes within 15 miles, 93621 leans more Republican than 2 of 5 neighbors.
93621 runs about 66 points more Republican than California as a whole. California leans Democratic overall, while 93621 is one of the few Republican-leaning pockets.
Politics vary noticeably by block within 93621. The east side is the most Republican-leaning (R+55) and the west side is the least Republican-leaning (R+44), a spread of about 11 points.
Why 93621 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 93621, not a ranked or complete list of what matters most.
93621 votes against the grain of California. California leans Democratic overall, while 93621 runs about 66 points more Republican. Rural areas vote Republican, and 93621 sits in the bottom quarter on density (about 4%, below 91% of zip codes). A high family-household share predicts Republican voting, and about 76% of households in 93621 are family households, above 82% of zip codes.
Population density and Republican lean
Places with low population density tend to lean Republican; 93621, CA sits in the bottom quarter nationally on this measure.
Why turnout in 93621 looks the way it does
Renters vote less often than owners. About 34% of households in 93621 rent, about 9 points above the U.S. average of 25%. 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.