51003 is a Republican stronghold. About 22% of voters here vote Democratic and 78% Republican.
About 87% of adults in 51003 typically vote, above the U.S. average of about 62%. Among adults in 51003, ~19% vote Democratic, ~68% Republican, and ~13% don't vote. The map below shows estimated turnout by block group.
How 51003 compares
Among zip codes within 15 miles, 51003 leans more Republican than 2 of 8 neighbors.
51003 runs about 43 points more Republican than Iowa as a whole.
Politics vary noticeably by block within 51003. The northeast side is the most Republican-leaning (R+68) and the east side is the least Republican-leaning (R+51), a spread of about 17 points.
Why 51003 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 51003, not a ranked or complete list of what matters most.
Car-dependent areas vote Republican. About 88% of residents in 51003 drive to work alone, about 14 points above the U.S. average of 74%.
Cancer-screening access and voter turnout
Places with high colon-cancer-screening access tend to turn out at a higher rate; 51003, IA sits in the top quarter nationally on this measure. Cancer screening does not drive turnout; it reflects income, insurance, and healthcare access.
Why turnout in 51003 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 51003 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 72%, about 12 points above the U.S. average of 60%. Homeowners vote more often than renters, and about 89% of households in 51003 own their home, above 83% of zip codes. High high-school completion lines up with higher turnout, and about 97% of adults in 51003 have completed high school, above 89% 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.