Brentwood leans slightly Democratic by roughly 14 points: about 57% of voters vote Democratic and 43% Republican.
About 78% of adults in Brentwood typically vote, above the U.S. average of about 62%. Among adults in Brentwood, ~44% vote Democratic, ~34% Republican, and ~22% don't vote. The map below shows estimated turnout by block group.
How Brentwood compares
Among cities within 25 miles, Brentwood leans more Democratic than 212 of 255 neighbors.
Brentwood runs about 15 points more Democratic than Pennsylvania as a whole. Pennsylvania is roughly evenly split, and Brentwood sits clearly on the Democratic side.
Politics vary noticeably by neighborhood within Brentwood. The northwest side is the most Democratic-leaning (D+22) and the east side is the least Democratic-leaning (D+5), a spread of about 17 points.
Why Brentwood 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 Brentwood, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 95% of residents in Brentwood live in densely developed areas, about 59 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and Brentwood sits in the top quarter (about 36%, above 84% of cities). A high never-married share predicts Democratic voting, and about 39% of adults in Brentwood have never been married, above 93% of cities.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; Brentwood, 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 Brentwood looks the way it does
Areas with high high-school completion turn out at higher rates. About 97% of adults in Brentwood have completed high school, about 6 points above the Pennsylvania average of 91%. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Baldwin, PA D+3
- Castle Shannon, PA D+10
- Mount Oliver, PA D+41
- Pleasant Hills, PA D+6
- Dormont, PA D+39
- West Homestead, PA D+19
- Homestead, PA D+49
- Munhall, PA D+17
- West Mifflin, PA D+5
- Dravosburg, PA R+6
Cities with Similar Populations
- Croydon, PA R+6
- Portland, MI R+31
- Maywood, NJ D+8
- Creswell, OR R+8
- Waynesboro, MS R+9
- Hull, MA D+15
- Muskegon Heights, MI D+77
- Berkeley Springs, WV R+55
- Colts Neck, NJ R+32
- Jacinto City, TX D+8
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.