San Jose is a Republican stronghold. About 22% of voters here vote Democratic and 78% Republican.
About 83% of adults in San Jose typically vote, above the U.S. average of about 62%. Among adults in San Jose, ~18% vote Democratic, ~64% Republican, and ~18% don't vote. The map below shows estimated turnout by block group.
How San Jose compares
Among cities within 25 miles, San Jose leans more Republican than 57 of 65 neighbors.
San Jose runs about 68 points more Republican than Illinois as a whole. Illinois leans Democratic overall, while San Jose is one of the few Republican-leaning pockets.
Why San Jose leans the way it does
This analysis examined 14,881 data points per city to find what predicts political lean and turnout. The items below are a few correlations that stood out for San Jose, not a ranked or complete list of what matters most.
San Jose votes against the grain of Illinois. Illinois leans Democratic overall, while San Jose runs about 68 points more Republican.
Population density and Republican lean
Places with low population density tend to lean Republican; San Jose, IL sits in the bottom quarter nationally on this measure.
Why turnout in San Jose looks the way it does
Turnout in San Jose sits close to the national pattern. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Natrona, IL R+58
- Delavan, IL R+43
- Emden, IL R+57
- Mason City, IL R+43
- Green Valley, IL R+46
- New Holland, IL R+58
- Hartsburg, IL R+58
- Teheran, IL R+58
- Parkland, IL R+54
- Forest City, IL R+52
Cities with Similar Populations
- Kadoka, SD R+57
- Dobbins, CA R+15
- Bath Springs, TN R+72
- Argusville, ND R+42
- Mora, NM D+26
- Mountain Hill, GA R+52
- Tunas, MO R+71
- Gallman, MS D+3
- Tull, AR R+75
- Andersonville, GA R+35
All Local Stats
Home Services
Sources and methodology
Precinct-level voting records used to fit the model come from Illinois State Board of 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.