Columbia County leans Republican by roughly 18 points: about 41% of voters vote Democratic and 59% Republican.
About 79% of adults in Columbia County typically vote, above the U.S. average of about 62%. Among adults in Columbia County, ~32% vote Democratic, ~47% Republican, and ~21% don't vote. The map below shows estimated turnout by block group.
How Columbia County compares
Among counties within 50 miles, Columbia County leans more Republican than 1 of 10 neighbors.
Columbia County runs about 16 points more Republican than Wisconsin as a whole.
Politics vary noticeably by city within Columbia County. The northeast side is the most Republican-leaning (R+38) and the southwest side is the least Republican-leaning (R+9), a spread of about 29 points.
Why Columbia County leans the way it does
Density, race composition, education, and family structure all sit close to their national averages in Columbia County. The lean here lands roughly where demographic data alone would predict.
Food insecurity and voter turnout
Places with low food insecurity tend to turn out at a higher rate; Columbia County, WI sits in the bottom quarter nationally on this measure. Food insecurity does not directly drive turnout; it reflects economic hardship, which lines up with lower voting.
Why turnout in Columbia County looks the way it does
Areas with strong routine healthcare access turn out at higher rates. Columbia 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 67%, about 7 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and about 94% of adults in Columbia County have completed high school, above 83% of counties. Learn more about the findings and methodology on the political spectrum map.
Nearby Counties
- Marquette County, WI R+36
- Sauk County, WI R+20
- Dane County, WI D+48
- Green Lake County, WI R+34
- Dodge County, WI R+30
- Adams County, WI R+26
- Jefferson County, WI R+21
- Waushara County, WI R+33
- Juneau County, WI R+31
- Fond du Lac County, WI R+23
Counties with Similar Populations
- Otsego County, NY R+5
- Pike County, PA R+21
- Pickaway County, OH R+41
- Huron County, OH R+44
- Genesee County, NY R+29
- Carson City, NV R+11
- Newton County, MO R+54
- Pike County, KY R+63
- Lawrence County, OH R+50
- Kenai Peninsula Borough, AK R+27
Sources and methodology
Precinct-level voting records used to fit the model come from Wisconsin Elections Commission, 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.