61605 is a Democratic stronghold. About 78% of voters here vote Democratic and 22% Republican.
About 48% of adults in 61605 typically vote, below the U.S. average of about 62%. Among adults in 61605, ~37% vote Democratic, ~11% Republican, and ~52% don't vote. The map below shows estimated turnout by block group.
How 61605 compares
Among zip codes within 15 miles, 61605 is the most Democratic-leaning.
61605 runs about 46 points more Democratic than Illinois as a whole.
Politics vary noticeably by block within 61605. The northeast side is the most Democratic-leaning (D+74) and the southwest side is the least Democratic-leaning (D+34), a spread of about 41 points.
Why 61605 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 61605, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 93% of residents in 61605 live in densely developed areas, about 56 points above the U.S. average of 36%. A high never-married share predicts Democratic voting, and about 50% of adults in 61605 have never been married, above 95% of zip codes.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; 61605, IL sits in the top tenth nationally on this measure. Paved ground does not change how people vote; it mostly reflects how urban and built-up a place is.
Why turnout in 61605 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 61605 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 40%, about 23 points below the Illinois average of 63%. Renters vote less often than owners, and about 58% of households in 61605 rent, compared to around 35% in nearby zip codes. High food insecurity lines up with lower turnout, and about 44% of adults in 61605 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 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.