93640 leans slightly Democratic by roughly 12 points: about 56% of voters vote Democratic and 44% Republican.
About 28% of adults in 93640 typically vote, below the U.S. average of about 62%. Among adults in 93640, ~16% vote Democratic, ~12% Republican, and ~72% don't vote. The map below shows estimated turnout by block group.
How 93640 compares
93640 sits in a sparsely populated area with few comparable zip codes nearby.
93640 runs about 8 points more Republican than California as a whole.
Politics vary noticeably by block within 93640. The east side runs the most Democratic (D+25) and the west side runs the most Republican (Even), a spread of about 27 points.
Why 93640 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 93640, not a ranked or complete list of what matters most.
Areas with many never-married adults vote Democratic. About 51% of adults in 93640 have never been married, well above similar-sized zip codes (around 29%).
Cancer-screening access and voter turnout
Places with low colon-cancer-screening access tend to turn out at a lower rate; 93640, CA sits in the bottom tenth nationally on this measure. Cancer screening does not drive turnout; it reflects income, insurance, and healthcare access.
Why turnout in 93640 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 93640 is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The dental-visit rate here is about 34%, about 28 points below the California average of 62%. Renters vote less often than owners, and about 59% of households in 93640 rent, about 34 points above the U.S. average of 25%. High food insecurity lines up with lower turnout, and about 51% of adults in 93640 report food insecurity, in the top fraction 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.