Millbourne leans heavily Democratic by roughly 38 points: about 69% of voters vote Democratic and 31% Republican.
About 33% of adults in Millbourne typically vote, below the U.S. average of about 62%. Among adults in Millbourne, ~23% vote Democratic, ~10% Republican, and ~67% don't vote. The map below shows estimated turnout by block group.
How Millbourne compares
Among cities within 25 miles, Millbourne leans more Democratic than 219 of 255 neighbors.
Millbourne runs about 40 points more Democratic than Pennsylvania as a whole. Pennsylvania is roughly evenly split, and Millbourne sits clearly on the Democratic side.
Why Millbourne leans the way it does
This analysis examined 14,881 data points per city to find what predicts political lean and turnout. The items below are a few correlations that stood out for Millbourne, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 92% of residents in Millbourne live in densely developed areas, about 55 points above the U.S. average of 36%. A high never-married share predicts Democratic voting, and about 36% of adults in Millbourne have never been married, above 88% of cities. Millbourne 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; Millbourne, PA sits in the top tenth 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 Millbourne looks the way it does
Renters vote less often than owners. About 66% of households in Millbourne rent, about 41 points above the U.S. average of 25%. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Upper Darby, PA D+53
- East Lansdowne, PA D+68
- Lansdowne, PA D+68
- Yeadon, PA D+86
- Wynnewood, PA D+61
- Merion Station, PA D+58
- Drexel Hill, PA D+32
- Darby, PA D+80
- Havertown, PA D+22
- Aldan, PA D+40
Cities with Similar Populations
- Ivey, GA R+61
- Casa Blanca, NM D+58
- Pembroke Township, IL D+62
- Floodwood, MN R+29
- Sunbury, NC R+27
- Bland, MO R+66
- Wolfeboro Falls, NH Even
- Colton, SD R+49
- Loire, TX R+23
- Sallis, MS Even
All Local Stats
Home Services
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.