84021 is a Republican stronghold. About 14% of voters here vote Democratic and 86% Republican.
About 56% of adults in 84021 typically vote, below the U.S. average of about 62%. Among adults in 84021, ~8% vote Democratic, ~48% Republican, and ~44% don't vote. The map below shows estimated turnout by block group.
How 84021 compares
Among zip codes within 15 miles, 84021 is the least Republican-leaning.
84021 runs about 50 points more Republican than Utah as a whole.
Politics vary noticeably by block within 84021. The northeast side is the most Republican-leaning (R+82) and the southwest side is the least Republican-leaning (R+61), a spread of about 22 points.
Why 84021 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 84021, not a ranked or complete list of what matters most.
Areas with many family households vote Republican. About 78% of households in 84021 are family households, about 12 points above the U.S. average of 67%. Rural areas vote Republican, and 84021 sits in the bottom quarter on density (about 5%, below 80% of zip codes). Low college attainment predicts Republican voting, and 84021 sits in the bottom quarter (about 17%, below 75% of zip codes).
Population density and Republican lean
Places with low population density tend to lean Republican; 84021, UT sits below the national average on this measure.
Why turnout in 84021 looks the way it does
Crowded housing lines up with lower turnout. About 4% of homes in 84021 have more than one occupant per room, 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 Utah Lieutenant Governor's Office, 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.