Chatham leans Democratic by roughly 18 points: about 59% of voters vote Democratic and 41% Republican.
About more than 99% of adults in Chatham typically vote, above the U.S. average of about 62%. Among adults in Chatham, ~58% vote Democratic, ~41% Republican, and ~1% don't vote. The map below shows estimated turnout by block group.
How Chatham compares
Among cities within 25 miles, Chatham leans more Democratic than 202 of 267 neighbors.
Chatham runs about 12 points more Democratic than New Jersey as a whole.
Politics vary noticeably by neighborhood within Chatham. The northeast side is the most Democratic-leaning (D+29) and the northwest side is the least Democratic-leaning (D+10), a spread of about 18 points.
Why Chatham 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 Chatham, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 83% of adults in Chatham hold a bachelor's degree, about 55 points above the U.S. average of 28%. Dense areas vote Democratic, and Chatham sits in the top fifth on density (about 84%, above 95% of cities).
Population density and Democratic lean
Places with high population density tend to lean Democratic; Chatham, NJ sits in the top tenth nationally on this measure.
Why turnout in Chatham looks the way it does
Areas with strong routine healthcare access turn out at higher rates. Chatham 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 79%, about 19 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and more than 99% of adults in Chatham have completed high school, above 98% of cities. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- New Providence, NJ D+19
- Madison, NJ D+22
- Green Village, NJ D+5
- Summit, NJ D+29
- Florham Park, NJ D+6
- Short Hills, NJ D+35
- Berkeley Heights, NJ D+11
- Mountainside, NJ Even
- New Vernon, NJ R+8
- Springfield, NJ D+18
Cities with Similar Populations
- Bastrop, LA D+9
- Sussex, WI R+23
- Portland, TX R+38
- North Canton, OH R+12
- Sellersburg, IN R+30
- Rossville, GA R+50
- Truckee, CA D+36
- Fruitville, FL R+19
- Lewistown, PA R+49
- Gautier, MS R+14
Sources and methodology
Precinct-level voting records used to fit the model come from New Jersey Division 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.