50166 leans heavily Republican by roughly 46 points: about 27% of voters vote Democratic and 73% Republican.
About 69% of adults in 50166 typically vote, above the U.S. average of about 62%. Among adults in 50166, ~19% vote Democratic, ~51% Republican, and ~30% don't vote. The map below shows estimated turnout by block group.
How 50166 compares
Among zip codes within 15 miles, 50166 leans more Republican than 8 of 11 neighbors.
50166 runs about 33 points more Republican than Iowa as a whole.
Why 50166 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 50166, not a ranked or complete list of what matters most.
Rural areas vote Republican. About 5% of residents in 50166 live in densely developed areas, about 11 points below the Iowa average of 16%. A high family-household share predicts Republican voting, and about 79% of households in 50166 are family households, above 90% of zip codes.
Walkability and Republican lean
Places with a low walkability score tend to lean Republican; 50166, IA sits in the bottom 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 50166 looks the way it does
Homeowners vote more often than renters. About 93% of households in 50166 own their home, about 12 points above the Iowa average of 81%. High high-school completion lines up with higher turnout, and about 97% of adults in 50166 have completed high school, above 86% of zip codes. 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 Iowa Secretary of State, 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.