18031 leans slightly Democratic by roughly 6 points: about 53% of voters vote Democratic and 47% Republican.
About 94% of adults in 18031 typically vote, above the U.S. average of about 62%. Among adults in 18031, ~50% vote Democratic, ~44% Republican, and ~6% don't vote. The map below shows estimated turnout by block group.
How 18031 compares
Among zip codes within 15 miles, 18031 leans more Democratic than 47 of 54 neighbors.
18031 runs about 8 points more Democratic than Pennsylvania as a whole.
Politics vary noticeably by block within 18031. The east side runs the most Democratic (D+16) and the northwest side runs the most Republican (R+15), a spread of about 31 points.
Why 18031 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 18031, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 53% of adults in 18031 hold a bachelor's degree, about 25 points above the U.S. average of 28%. Density combined with diversity predicts Democratic voting, and non-Hispanic white share in 18031 is about 63%, compared to around 81% in nearby zip codes.
Population density and Democratic lean
Places with high population density tend to lean Democratic; 18031, PA sits in the top quarter nationally on this measure.
Why turnout in 18031 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 18031 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 70%, about 10 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and about 98% of adults in 18031 have completed high school, above 93% 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 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.