50138 leans heavily Republican by roughly 38 points: about 31% of voters vote Democratic and 69% Republican.
About 91% of adults in 50138 typically vote, above the U.S. average of about 62%. Among adults in 50138, ~28% vote Democratic, ~63% Republican, and ~9% don't vote. The map below shows estimated turnout by block group.
How 50138 compares
Among zip codes within 15 miles, 50138 leans more Republican than 2 of 12 neighbors.
50138 runs about 24 points more Republican than Iowa as a whole.
Politics vary noticeably by block within 50138. The southeast side is the most Republican-leaning (R+47) and the east side is the least Republican-leaning (R+30), a spread of about 17 points.
Why 50138 leans the way it does
Density, race composition, education, and family structure all sit close to their national averages in 50138. The lean here lands roughly where demographic data alone would predict.
Food insecurity and voter turnout
Places with low food insecurity tend to turn out at a higher rate; 50138, IA sits below the national average on this measure. Food insecurity does not directly drive turnout; it reflects economic hardship, which lines up with lower voting.
Why turnout in 50138 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 50138 is in the top quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The dental-visit rate here is about 69%, about 9 points above the U.S. average of 60%. 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.