Romeoville, IL Political Map | Democrat & Republican Areas in Romeoville

By the BestNeighborhood data science team. Last updated May 2026.

Romeoville leans slightly Democratic by roughly 14 points: about 57% of voters vote Democratic and 43% Republican.

 

About 60% of adults in Romeoville typically vote, near the U.S. average of about 62%. Among adults in Romeoville, ~34% vote Democratic, ~26% Republican, and ~40% don't vote. The map below shows estimated turnout by block group.

How Romeoville compares

Among cities within 25 miles, Romeoville leans more Democratic than 97 of 154 neighbors.

Politically, Romeoville sits close to the rest of Illinois.

Politics vary noticeably by neighborhood within Romeoville. The southwest side runs the most Democratic (D+22) and the southeast side runs the most Republican (Even), a spread of about 23 points.

Why Romeoville 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 Romeoville, not a ranked or complete list of what matters most.

Dense areas vote Democratic. About 87% of residents in Romeoville live in densely developed areas, about 51 points above the U.S. average of 36%. A high never-married share predicts Democratic voting, and about 38% of adults in Romeoville have never been married, above 92% of cities.

Paved land cover and Democratic lean

Places with extensive paved surfaces tend to lean Democratic; Romeoville, 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 Romeoville looks the way it does

Areas with limited routine healthcare access turn out at lower rates. Romeoville is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. Learn more about the findings and methodology on the political spectrum map.

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.