Nantucket County leans Democratic by roughly 24 points: about 62% of voters vote Democratic and 38% Republican.
About 85% of adults in Nantucket County typically vote, above the U.S. average of about 62%. Among adults in Nantucket County, ~53% vote Democratic, ~32% Republican, and ~15% don't vote. The map below shows estimated turnout by block group.
How Nantucket County compares
Nantucket County sits in a sparsely populated area with few comparable counties nearby.
Politically, Nantucket County sits close to the rest of Massachusetts.
Politics vary noticeably by city within Nantucket County. The north side is the most Democratic-leaning (D+53) and the south side is the least Democratic-leaning (D+11), a spread of about 42 points.
Why Nantucket County leans the way it does
This analysis examined 14,881 data points per county to find what predicts political lean and turnout. The items below are a few correlations that stood out for Nantucket County, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 64% of residents in Nantucket County live in densely developed areas, about 28 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and Nantucket County sits in the top quarter (about 56%, in the top fraction of counties). A high never-married share predicts Democratic voting, and about 34% of adults in Nantucket County have never been married, above 82% of counties.
Park access and Democratic lean
Places with heavy park coverage tend to lean Democratic; Nantucket County, MA sits in the top quarter nationally on this measure. Park access does not change how people vote; it tends to track denser, higher-income areas.
Why turnout in Nantucket County looks the way it does
Areas with strong routine healthcare access turn out at higher rates. Nantucket County 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 75%, about 15 points above the U.S. average of 60%. Learn more about the findings and methodology on the political spectrum map.
Nearby Counties
- Dukes County, MA D+41
- Barnstable County, MA D+20
- Newport County, RI D+23
- Bristol County, MA Even
- Plymouth County, MA D+11
- Bristol County, RI D+17
- Kent County, RI D+5
- Washington County, RI D+11
- Providence County, RI D+20
- Norfolk County, MA D+30
Counties with Similar Populations
- Knott County, KY R+67
- Clay County, AL R+65
- Saline County, NE R+38
- Hardy County, WV R+61
- Smith County, MS R+59
- Choctaw County, OK R+54
- Franklin County, ID R+77
- Gulf County, FL R+56
- Rusk County, WI R+38
- Cedar County, MO R+65
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.