15140 leans Democratic by roughly 18 points: about 59% of voters vote Democratic and 41% Republican.
About 60% of adults in 15140 typically vote, near the U.S. average of about 62%. Among adults in 15140, ~35% vote Democratic, ~25% Republican, and ~40% don't vote. The map below shows estimated turnout by block group.
How 15140 compares
Among zip codes within 15 miles, 15140 leans more Democratic than 66 of 100 neighbors.
15140 runs about 19 points more Democratic than Pennsylvania as a whole. Pennsylvania is roughly evenly split, and 15140 sits clearly on the Democratic side.
Politics vary noticeably by block within 15140. The southwest side is the most Democratic-leaning (D+31) and the northwest side is the least Democratic-leaning (Even), a spread of about 31 points.
Why 15140 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 15140, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 88% of residents in 15140 live in densely developed areas, about 52 points above the U.S. average of 36%. A high never-married share predicts Democratic voting, and about 48% of adults in 15140 have never been married, above 94% of zip codes. 15140 runs against the grain of Pennsylvania, a Democratic-leaning outlier in a roughly evenly split state.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; 15140, PA sits in the top quarter nationally on this measure. Paved ground does not change how people vote; it mostly reflects how urban and built-up a place is.
Why turnout in 15140 looks the way it does
Renters vote less often than owners. About 56% of households in 15140 rent, about 31 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 Pennsylvania Department of State, Bureau of 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.