South Dartmouth leans slightly Democratic by roughly 8 points: about 54% of voters vote Democratic and 46% Republican.
About 85% of adults in South Dartmouth typically vote, above the U.S. average of about 62%. Among adults in South Dartmouth, ~46% vote Democratic, ~39% Republican, and ~15% don't vote. The map below shows estimated turnout by block group.
How South Dartmouth compares
Among cities within 25 miles, South Dartmouth leans more Democratic than 54 of 87 neighbors.
South Dartmouth runs about 17 points more Republican than Massachusetts as a whole.
Politics vary noticeably by neighborhood within South Dartmouth. The west side runs the most Democratic (D+20) and the north side runs the most Republican (R+10), a spread of about 30 points.
Why South Dartmouth 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 South Dartmouth, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 45% of adults in South Dartmouth hold a bachelor's degree, about 16 points above the U.S. average of 28%. Dense areas vote Democratic, and South Dartmouth sits in the top fifth on density (about 60%, above 90% of cities).
Preventive-care access and voter turnout
Places with strong routine preventive-care access tend to turn out at a higher rate; South Dartmouth, MA sits in the top tenth nationally on this measure. Dental visits do not drive turnout; the rate reflects income, insurance, and healthcare access, which line up with who votes.
Why turnout in South Dartmouth looks the way it does
Areas with strong routine healthcare access turn out at higher rates. South Dartmouth 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 73%, about 13 points above the U.S. average of 60%. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Smith Mills, MA R+5
- Head of Westport, MA R+5
- New Bedford, MA D+8
- North Dartmouth, MA R+4
- Dartmouth, MA R+12
- Cow Yard, MA D+8
- Fairhaven, MA R+3
- South Westport, MA D+3
Cities with Similar Populations
- Newaygo, MI R+40
- Holbrook, MA D+12
- Venus, TX R+42
- Ringwood, NJ R+14
- Crystal Lake, FL R+11
- View Park-Windsor Hills, CA D+84
- Athol, MA R+8
- Prince George, VA D+7
- Rossville, MD D+45
- Mohnton, PA R+28
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.