Kootenai County leans heavily Republican by roughly 46 points: about 27% of voters vote Democratic and 73% Republican.
About 78% of adults in Kootenai County typically vote, above the U.S. average of about 62%. Among adults in Kootenai County, ~21% vote Democratic, ~57% Republican, and ~22% don't vote. The map below shows estimated turnout by block group.
How Kootenai County compares
Among counties within 50 miles, Kootenai County leans more Republican than 4 of 5 neighbors.
Kootenai County runs about 10 points more Republican than Idaho as a whole.
Politics vary noticeably by city within Kootenai County. The northwest side is the most Republican-leaning (R+59) and the south side is the least Republican-leaning (R+14), a spread of about 45 points.
Why Kootenai 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 Kootenai County, not a ranked or complete list of what matters most.
Kootenai County votes Republican even though it is densely developed (about 65%, far above the Idaho average of 18%). State and regional patterns outweigh the Democratic lean that density usually predicts here. A high family-household share predicts Republican voting, and about 70% of households in Kootenai County are family households, above 79% of counties.
High-school completion and voter turnout
Places with high-school-completion-heavy adults tend to turn out at a higher rate; Kootenai County, ID sits in the top quarter nationally on this measure.
Why turnout in Kootenai County looks the way it does
Areas with strong routine healthcare access turn out at higher rates. Kootenai 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 66%, about 6 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and about 95% of adults in Kootenai County have completed high school, above 90% of counties. Learn more about the findings and methodology on the political spectrum map.
Nearby Counties
- Spokane County, WA R+3
- Benewah County, ID R+60
- Bonner County, ID R+44
- Shoshone County, ID R+43
- Pend Oreille County, WA R+38
- Stevens County, WA R+37
- Whitman County, WA D+16
- Latah County, ID R+4
- Lincoln County, WA R+54
- Boundary County, ID R+64
Counties with Similar Populations
- Alamance County, NC R+4
- Winnebago County, WI R+3
- McLean County, IL D+5
- Kent County, RI D+5
- Pitt County, NC D+17
- Guadalupe County, TX R+23
- Midland County, TX R+48
- Carroll County, MD R+24
- Porter County, IN R+11
- Wyandotte County, KS D+26
Sources and methodology
Precinct-level voting records used to fit the model come from Idaho 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.