61102 leans heavily Democratic by roughly 32 points: about 66% of voters vote Democratic and 34% Republican.
About 54% of adults in 61102 typically vote, below the U.S. average of about 62%. Among adults in 61102, ~36% vote Democratic, ~18% Republican, and ~46% don't vote. The map below shows estimated turnout by block group.
How 61102 compares
Among zip codes within 15 miles, 61102 leans more Democratic than 24 of 25 neighbors.
61102 runs about 21 points more Democratic than Illinois as a whole.
Politics vary noticeably by block within 61102. The north side runs the most Democratic (D+69) and the southwest side runs the most Republican (R+27), a spread of about 96 points.
Why 61102 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 61102, not a ranked or complete list of what matters most.
Density combined with diversity predicts Democratic voting. Non-Hispanic white share in 61102 is about 41%, about 31 points below the U.S. average of 72%. A high never-married share predicts Democratic voting, and about 44% of adults in 61102 have never been married, above 92% of zip codes.
Population density and Democratic lean
Places with high population density tend to lean Democratic; 61102, IL sits in the top quarter nationally on this measure.
Why turnout in 61102 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 61102 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 46%, about 17 points below the Illinois average of 63%. Renters vote less often than owners, and about 36% of households in 61102 rent, above 83% of zip codes. High food insecurity lines up with lower turnout, and about 37% of adults in 61102 report food insecurity, above 97% 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 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.