81643 is a Republican stronghold. About 23% of voters here vote Democratic and 77% Republican.
About 71% of adults in 81643 typically vote, above the U.S. average of about 62%. Among adults in 81643, ~16% vote Democratic, ~55% Republican, and ~29% don't vote. The map below shows estimated turnout by block group.
How 81643 compares
Among zip codes within 15 miles, 81643 leans more Republican than 3 of 4 neighbors.
81643 runs about 65 points more Republican than Colorado as a whole. Colorado leans Democratic overall, while 81643 is one of the few Republican-leaning pockets.
Why 81643 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 81643, not a ranked or complete list of what matters most.
81643 votes against the grain of Colorado. Colorado leans Democratic overall, while 81643 runs about 65 points more Republican. Rural areas vote Republican, and 81643 sits in the bottom quarter on density (about 1%, below 97% of zip codes). A high family-household share predicts Republican voting, and about 76% of households in 81643 are family households, above 82% of zip codes.
Paved land cover and Republican lean
Places with little paved surface tend to lean Republican; 81643, CO sits in the bottom tenth nationally on this measure. Paved ground does not change how people vote; it mostly reflects how urban and built-up a place is.
Why turnout in 81643 looks the way it does
Turnout in 81643 sits close to the national pattern. Routine healthcare access, homeownership, education, and food security all land near their national averages here. 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 Colorado 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.