South Wilmington leans heavily Republican by roughly 38 points: about 31% of voters vote Democratic and 69% Republican.
About 78% of adults in South Wilmington typically vote, above the U.S. average of about 62%. Among adults in South Wilmington, ~24% vote Democratic, ~54% Republican, and ~22% don't vote. The map below shows estimated turnout by block group.
How South Wilmington compares
Among cities within 25 miles, South Wilmington leans more Republican than 23 of 65 neighbors.
South Wilmington runs about 50 points more Republican than Illinois as a whole. Illinois leans Democratic overall, while South Wilmington is one of the few Republican-leaning pockets.
Why South Wilmington 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 South Wilmington, not a ranked or complete list of what matters most.
Car-dependent areas vote Republican. About 89% of residents in South Wilmington drive to work alone, about 16 points above the U.S. average of 74%. Low college attainment predicts Republican voting, and South Wilmington sits in the bottom quarter (about 15%, below 78% of cities). South Wilmington runs against the grain of Illinois, a Republican-leaning pocket in a Democratic-leaning state.
Park access and Republican lean
Places with low park coverage tend to lean Republican; South Wilmington, IL sits below the national average on this measure. Park access does not change how people vote; it tends to track denser, higher-income areas.
Why turnout in South Wilmington looks the way it does
Turnout in South Wilmington sits close to the national pattern. Routine healthcare access, homeownership, education, and food security all land near their national averages here. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Gardner, IL R+32
- Braceville, IL R+31
- Reddick, IL R+49
- Godley, IL R+40
- Essex, IL R+47
- Braidwood, IL R+32
- Diamond, IL R+33
- Coal City, IL R+30
- Union Hill, IL R+50
Cities with Similar Populations
- Vera Cruz, IN R+70
- Elm Park, LA R+62
- Sunshine, LA D+14
- Rock View, WV R+68
- Glenmore, WV R+50
- Newsoms, VA R+22
- Sunshine, NM R+27
- Copeland, KS R+76
- Penasco, NM D+20
- Sod, WV R+63
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.