50104 is a Republican stronghold. About 23% of voters here vote Democratic and 77% Republican.
About 85% of adults in 50104 typically vote, above the U.S. average of about 62%. Among adults in 50104, ~20% vote Democratic, ~65% Republican, and ~15% don't vote. The map below shows estimated turnout by block group.
How 50104 compares
Among zip codes within 15 miles, 50104 leans more Republican than 12 of 13 neighbors.
50104 runs about 41 points more Republican than Iowa as a whole.
Why 50104 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 50104, not a ranked or complete list of what matters most.
Rural areas vote Republican. About 6% of residents in 50104 live in densely developed areas, about 11 points below the Iowa average of 16%. Low college attainment predicts Republican voting, and 50104 sits in the bottom quarter (about 13%, below 86% of zip codes).
Population density and Republican lean
Places with low population density tend to lean Republican; 50104, IA sits in the bottom quarter nationally on this measure.
Why turnout in 50104 looks the way it does
Homeowners vote more often than renters. About 89% of households in 50104 own their home, about 7 points above the Iowa average of 81%. 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.