01129 leans Democratic by roughly 20 points: about 60% of voters vote Democratic and 40% Republican.
About 77% of adults in 01129 typically vote, above the U.S. average of about 62%. Among adults in 01129, ~46% vote Democratic, ~31% Republican, and ~23% don't vote. The map below shows estimated turnout by block group.
How 01129 compares
Among zip codes within 15 miles, 01129 leans more Democratic than 22 of 37 neighbors.
01129 runs about 6 points more Republican than Massachusetts as a whole.
Politics vary noticeably by block within 01129. The north side is the most Democratic-leaning (D+30) and the southeast side is the least Democratic-leaning (D+9), a spread of about 22 points.
Why 01129 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 01129, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 76% of residents in 01129 live in densely developed areas, about 40 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and 01129 sits in the top quarter (about 37%, above 77% of zip codes). A high never-married share predicts Democratic voting, and about 36% of adults in 01129 have never been married, above 81% of zip codes.
Walkability and Democratic lean
Places with a highly walkable street grid tend to lean Democratic; 01129, MA sits in the top quarter nationally on this measure. A walkable street grid does not change how people vote; it mostly reflects how urban a place is.
Why turnout in 01129 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 01129 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 68%, about 8 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 Massachusetts Secretary of the Commonwealth, 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.