50315 leans slightly Democratic by roughly 14 points: about 57% of voters vote Democratic and 43% Republican.
About 62% of adults in 50315 typically vote, near the U.S. average of about 62%. Among adults in 50315, ~35% vote Democratic, ~27% Republican, and ~38% don't vote. The map below shows estimated turnout by block group.
How 50315 compares
Among zip codes within 15 miles, 50315 leans more Democratic than 25 of 34 neighbors.
50315 runs about 27 points more Democratic than Iowa as a whole. Iowa leans Republican overall, while 50315 is one of the few Democratic-leaning pockets.
Politics vary noticeably by block within 50315. The northwest side is the most Democratic-leaning (D+21) and the southwest side is the least Democratic-leaning (D+3), a spread of about 18 points.
Why 50315 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 50315, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 96% of residents in 50315 live in densely developed areas, about 60 points above the U.S. average of 36%. A high never-married share predicts Democratic voting, and about 38% of adults in 50315 have never been married, above 84% of zip codes. 50315 runs against the grain of Iowa, a Democratic-leaning pocket in a Republican-leaning state.
Walkability and Democratic lean
Places with a highly walkable street grid tend to lean Democratic; 50315, IA sits in the top tenth 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 50315 looks the way it does
Turnout in 50315 sits close to the national pattern. Routine healthcare access, homeownership, education, and food security all land near their national averages here. 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.