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

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

Posen leans heavily Democratic by roughly 32 points: about 66% of voters vote Democratic and 34% Republican.

 

About 44% of adults in Posen typically vote, below the U.S. average of about 62%. Among adults in Posen, ~29% vote Democratic, ~15% Republican, and ~56% don't vote. The map below shows estimated turnout by block group.

How Posen compares

Among cities within 25 miles, Posen leans more Democratic than 96 of 141 neighbors.

Posen runs about 22 points more Democratic than Illinois as a whole.

Politics vary noticeably by neighborhood within Posen. The northwest side is the most Democratic-leaning (D+41) and the south side is the least Democratic-leaning (D+26), a spread of about 15 points.

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

Dense areas vote Democratic. About 99% of residents in Posen live in densely developed areas, about 62 points above the U.S. average of 36%. A high never-married share predicts Democratic voting, and about 45% of adults in Posen have never been married, above 96% of cities.

Population density and Democratic lean

Places with high population density tend to lean Democratic; Posen, IL sits in the top tenth nationally on this measure.

Why turnout in Posen looks the way it does

Areas with limited routine healthcare access turn out at lower rates. Posen is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The uninsured rate here is about 20%, about 12 points above the Illinois average of 8%. Renters vote less often than owners, and about 31% of households in Posen rent, above 85% of cities. High food insecurity lines up with lower turnout, and about 28% of adults in Posen report food insecurity, above 94% of cities. 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.