83440 leans heavily Republican by roughly 34 points: about 33% of voters vote Democratic and 67% Republican.
About 55% of adults in 83440 typically vote, below the U.S. average of about 62%. Among adults in 83440, ~18% vote Democratic, ~37% Republican, and ~45% don't vote. The map below shows estimated turnout by block group.
How 83440 compares
Among zip codes within 15 miles, 83440 leans more Republican than 1 of 10 neighbors.
Politically, 83440 sits close to the rest of Idaho.
Politics vary noticeably by block within 83440. The west side is the most Republican-leaning (R+67) and the east side is the least Republican-leaning (R+30), a spread of about 38 points.
Why 83440 leans the way it does
This analysis examined 14,881 data points per zip code to find what predicts political lean and turnout. The items below are a few correlations that stood out for 83440, not a ranked or complete list of what matters most.
83440 votes Republican even though it is densely developed (about 68%, far above the Idaho average of 18%). State and regional patterns outweigh the Democratic lean that density usually predicts here.
Never-married share, developed land, and voter turnout
Places that combine a never-married-heavy adult population and a heavily developed built environment tend to turn out at a lower rate, as 83440, ID does.
Why turnout in 83440 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 83440 is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. Renters vote less often than owners, and about 63% of households in 83440 rent, compared to around 25% in nearby zip codes. High food insecurity lines up with lower turnout, and about 21% of adults in 83440 report food insecurity, above 83% of zip codes. Learn more about the findings and methodology on the political spectrum map.
Nearby Zip Codes
Zip Codes with Similar Populations
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.