83703 leans Democratic by roughly 24 points: about 62% of voters vote Democratic and 38% Republican.
About 75% of adults in 83703 typically vote, above the U.S. average of about 62%. Among adults in 83703, ~46% vote Democratic, ~29% Republican, and ~25% don't vote. The map below shows estimated turnout by block group.
How 83703 compares
Among zip codes within 15 miles, 83703 leans more Democratic than 11 of 14 neighbors.
83703 runs about 60 points more Democratic than Idaho as a whole. Idaho leans Republican overall, while 83703 is one of the few Democratic-leaning pockets.
Politics vary noticeably by block within 83703. The east side is the most Democratic-leaning (D+43) and the northeast side is the least Democratic-leaning (D+11), a spread of about 31 points.
Why 83703 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 83703, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 88% of residents in 83703 live in densely developed areas, about 52 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and 83703 sits in the top quarter (about 52%, above 90% of zip codes). 83703 runs against the grain of Idaho, a Democratic-leaning pocket in a Republican-leaning state.
Preventive-care access and voter turnout
Places with strong routine preventive-care access tend to turn out at a higher rate; 83703, ID sits in the top tenth nationally on this measure. Dental visits do not drive turnout; the rate reflects income, insurance, and healthcare access, which line up with who votes.
Why turnout in 83703 looks the way it does
Areas with strong routine healthcare access turn out at higher rates. 83703 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 73%, about 13 points above the U.S. average of 60%. High high-school completion lines up with higher turnout, and about 96% of adults in 83703 have completed high school, above 84% 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.