18915 leans slightly Democratic by roughly 14 points: about 57% of voters vote Democratic and 43% Republican.
About 85% of adults in 18915 typically vote, above the U.S. average of about 62%. Among adults in 18915, ~48% vote Democratic, ~37% Republican, and ~15% don't vote. The map below shows estimated turnout by block group.
How 18915 compares
Among zip codes within 15 miles, 18915 leans more Democratic than 40 of 68 neighbors.
18915 runs about 17 points more Democratic than Pennsylvania as a whole. Pennsylvania is roughly evenly split, and 18915 sits clearly on the Democratic side.
Politics vary noticeably by block within 18915. The southeast side is the most Democratic-leaning (D+19) and the west side is the least Democratic-leaning (D+4), a spread of about 15 points.
Why 18915 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 18915, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 88% of residents in 18915 live in densely developed areas, about 51 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and 18915 sits in the top quarter (about 50%, above 89% of zip codes). 18915 runs against the grain of Pennsylvania, a Democratic-leaning outlier in a roughly evenly split state.
Population density, never-married share, and Democratic lean
Places that combine high population density and a low never-married share tend to lean Democratic, as 18915, PA does.
Why turnout in 18915 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 18915 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 71%, about 11 points above the U.S. average of 60%. 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.