Sheffield leans heavily Republican by roughly 34 points: about 33% of voters vote Democratic and 67% Republican.
About 82% of adults in Sheffield typically vote, above the U.S. average of about 62%. Among adults in Sheffield, ~27% vote Democratic, ~55% Republican, and ~18% don't vote. The map below shows estimated turnout by block group.
How Sheffield compares
Among cities within 25 miles, Sheffield leans more Republican than 14 of 52 neighbors.
Sheffield runs about 45 points more Republican than Illinois as a whole. Illinois leans Democratic overall, while Sheffield is one of the few Republican-leaning pockets.
Politics vary noticeably by neighborhood within Sheffield. The northwest side is the most Republican-leaning (R+46) and the south side is the least Republican-leaning (R+31), a spread of about 15 points.
Why Sheffield 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 Sheffield, not a ranked or complete list of what matters most.
Sheffield votes against the grain of Illinois. Illinois leans Democratic overall, while Sheffield runs about 45 points more Republican.
Population density and Democratic lean
Places with high population density tend to lean Democratic; Sheffield, IL sits above the national average on this measure.
Why turnout in Sheffield looks the way it does
Turnout in Sheffield 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
- Buda, IL R+45
- Neponset, IL R+43
- Mineral, IL R+43
- Manlius, IL R+48
- Osceola, IL R+43
- Annawan, IL R+37
- Wyanet, IL R+32
- Thomas, IL R+47
- Lombardville, IL R+49
- New Bedford, IL R+46
Cities with Similar Populations
- Falls Of Rough, KY R+62
- Rocksprings, TX R+34
- Fish Creek, WI D+22
- Tunbridge, VT D+12
- Tontogany, OH R+41
- Porter, NC R+51
- Graettinger, IA R+45
- Elmhurst, WI R+48
- Lerona, WV R+68
- Graingers, NC R+16
All Local Stats
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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.