Warren County leans Republican by roughly 16 points: about 42% of voters vote Democratic and 58% Republican.
About 77% of adults in Warren County typically vote, above the U.S. average of about 62%. Among adults in Warren County, ~32% vote Democratic, ~45% Republican, and ~23% don't vote. The map below shows estimated turnout by block group.
How Warren County compares
Among counties within 50 miles, Warren County leans more Republican than 13 of 17 neighbors.
Warren County runs about 22 points more Republican than New Jersey as a whole. New Jersey leans Democratic overall, while Warren County is one of the few Republican-leaning pockets.
Politics vary noticeably by city within Warren County. The north side is the most Republican-leaning (R+35) and the southwest side is the least Republican-leaning (R+4), a spread of about 31 points.
Why Warren 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 Warren County, not a ranked or complete list of what matters most.
Warren County votes Republican even though it is densely developed (about 48%, modestly below the New Jersey average of 61%). State and regional patterns outweigh the Democratic lean that density usually predicts here. Warren County runs against the grain of New Jersey, a Republican-leaning pocket in a Democratic-leaning state.
Walkability and Democratic lean
Places with a highly walkable street grid tend to lean Democratic; Warren County, NJ 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 Warren County looks the way it does
Areas with strong routine healthcare access turn out at higher rates. Warren 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 68%, about 8 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and about 94% of adults in Warren County have completed high school, above 83% of counties. Learn more about the findings and methodology on the political spectrum map.
Nearby Counties
- Hunterdon County, NJ R+6
- Northampton County, PA Even
- Monroe County, PA Even
- Morris County, NJ Even
- Sussex County, NJ R+23
- Somerset County, NJ D+15
- Lehigh County, PA D+6
- Pike County, PA R+21
- Carbon County, PA R+35
- Bucks County, PA Even
Counties with Similar Populations
- LaSalle County, IL R+21
- Terrebonne Parish, LA R+42
- Hanover County, VA R+21
- Pennington County, SD R+28
- Eaton County, MI R+8
- Madison County, MS R+5
- Bartow County, GA R+46
- Miami County, OH R+42
- Bradley County, TN R+48
- Mercer County, PA R+27
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.