63042 leans heavily Democratic by roughly 38 points: about 69% of voters vote Democratic and 31% Republican.
About 60% of adults in 63042 typically vote, near the U.S. average of about 62%. Among adults in 63042, ~41% vote Democratic, ~19% Republican, and ~40% don't vote. The map below shows estimated turnout by block group.
How 63042 compares
Among zip codes within 15 miles, 63042 leans more Democratic than 23 of 59 neighbors.
63042 runs about 57 points more Democratic than Missouri as a whole. Missouri leans Republican overall, while 63042 is one of the few Democratic-leaning pockets.
Politics vary noticeably by block within 63042. The southeast side is the most Democratic-leaning (D+60) and the northwest side is the least Democratic-leaning (D+11), a spread of about 49 points.
Why 63042 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 63042, not a ranked or complete list of what matters most.
Density combined with diversity predicts Democratic voting. Non-Hispanic white share in 63042 is about 44%, about 28 points below the U.S. average of 72%. A high never-married share predicts Democratic voting, and about 49% of adults in 63042 have never been married, above 95% of zip codes. 63042 runs against the grain of Missouri, a Democratic-leaning pocket in a Republican-leaning state.
Walkability and Democratic lean
Places with a highly walkable street grid tend to lean Democratic; 63042, MO sits in the top 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 63042 looks the way it does
Renters vote less often than owners. About 44% of households in 63042 rent, about 19 points above the U.S. average of 25%. 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 Missouri 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.