Arlington is a Democratic stronghold. About 84% of voters here vote Democratic and 16% Republican.
About 83% of adults in Arlington typically vote, above the U.S. average of about 62%. Among adults in Arlington, ~70% vote Democratic, ~13% Republican, and ~17% don't vote. The map below shows estimated turnout by block group.
How Arlington compares
Among cities within 25 miles, Arlington leans more Democratic than 151 of 157 neighbors.
Arlington runs about 44 points more Democratic than Massachusetts as a whole.
Politics vary noticeably by neighborhood within Arlington. The southwest side is the most Democratic-leaning (D+76) and the northeast side is the least Democratic-leaning (D+63), a spread of about 13 points.
Why Arlington 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 Arlington, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 76% of adults in Arlington hold a bachelor's degree, about 48 points above the U.S. average of 28%. Dense areas vote Democratic, and Arlington sits in the top fifth on density (about 98%, above 98% of cities). A high never-married share predicts Democratic voting, and about 31% of adults in Arlington have never been married, above 76% of cities.
Population density and Democratic lean
Places with high population density tend to lean Democratic; Arlington, MA sits in the top tenth nationally on this measure.
Why turnout in Arlington looks the way it does
Areas with strong routine healthcare access turn out at higher rates. Arlington 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 78%, about 18 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and about 98% of adults in Arlington have completed high school, above 95% of cities. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Belmont, MA D+63
- Winchester, MA D+51
- Watertown, MA D+77
- Medford, MA D+46
- Watertown Town, MA D+57
- Somerville, MA D+69
- Lexington, MA D+54
- Cambridge, MA D+74
- Waltham, MA D+43
- Allston, MA D+67
Cities with Similar Populations
- Cape Girardeau, MO R+17
- Lake Oswego, OR D+45
- Tucker, GA D+36
- Lititz, PA R+16
- Kalispell, MT R+33
- Brighton, MI R+16
- Lakeside, CA R+23
- Mableton, GA D+46
- Springfield, VA D+28
- Jamesburg, NJ R+4
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.