61704 leans slightly Democratic by roughly 8 points: about 54% of voters vote Democratic and 46% Republican.
About 77% of adults in 61704 typically vote, above the U.S. average of about 62%. Among adults in 61704, ~42% vote Democratic, ~35% Republican, and ~23% don't vote. The map below shows estimated turnout by block group.
How 61704 compares
Among zip codes within 15 miles, 61704 leans more Democratic than 13 of 15 neighbors.
Politically, 61704 sits close to the rest of Illinois.
Politics vary noticeably by block within 61704. The northwest side runs the most Democratic (D+20) and the southeast side runs the most Republican (R+15), a spread of about 35 points.
Why 61704 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 61704, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 57% of adults in 61704 hold a bachelor's degree, about 28 points above the U.S. average of 28%. Dense areas vote Democratic, and 61704 sits in the top fifth on density (about 83%, above 84% of zip codes).
Walkability and Democratic lean
Places with a highly walkable street grid tend to lean Democratic; 61704, IL sits in the top quarter nationally on this measure. A walkable street grid does not change how people vote; it mostly reflects how urban a place is.
Why turnout in 61704 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 61704 is in the top quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The dental-visit rate here is about 69%, about 9 points above the U.S. average of 60%. 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.