Columbia County is a Republican stronghold. About 24% of voters here vote Democratic and 76% Republican.
About 71% of adults in Columbia County typically vote, above the U.S. average of about 62%. Among adults in Columbia County, ~17% vote Democratic, ~54% Republican, and ~29% 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 4 of 5 neighbors.
Columbia County runs about 70 points more Republican than Washington as a whole. Washington leans Democratic overall, while Columbia County is one of the few Republican-leaning pockets.
Politics vary noticeably by city within Columbia County. The northwest side is the most Republican-leaning (R+70) and the south side is the least Republican-leaning (R+50), a spread of about 20 points.
Why Columbia 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 Columbia County, not a ranked or complete list of what matters most.
Columbia County votes against the grain of Washington. Washington leans Democratic overall, while Columbia County runs about 70 points more Republican. Rural areas vote Republican, and Columbia County sits in the bottom quarter on density (about 9%, below 84% of counties).
Population density and Republican lean
Places with low population density tend to lean Republican; Columbia County, WA sits in the bottom quarter nationally on this measure.
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 65%, about 5 points above the U.S. average of 60%. Learn more about the findings and methodology on the political spectrum map.
Nearby Counties
- Garfield County, WA R+58
- Walla Walla County, WA R+7
- Asotin County, WA R+29
- Whitman County, WA D+16
- Nez Perce County, ID R+35
- Franklin County, WA R+16
- Latah County, ID R+4
- Umatilla County, OR R+34
- Benton County, WA R+21
- Adams County, WA R+31
Counties with Similar Populations
- Mason County, TX R+56
- Red Lake County, MN R+47
- Wells County, ND R+58
- Kearny County, KS R+71
- Edmunds County, SD R+60
- Pierce County, ND R+47
- Gregory County, SD R+65
- Corson County, SD D+38
- Sioux County, ND D+54
- Chase County, NE R+71
Sources and methodology
Precinct-level voting records used to fit the model come from Washington Secretary of State, 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.