77420 is a Republican stronghold. About 24% of voters here vote Democratic and 76% Republican.
About 79% of adults in 77420 typically vote, above the U.S. average of about 62%. Among adults in 77420, ~19% vote Democratic, ~60% Republican, and ~21% don't vote. The map below shows estimated turnout by block group.
How 77420 compares
Among zip codes within 15 miles, 77420 leans more Republican than 7 of 8 neighbors.
77420 runs about 39 points more Republican than Texas as a whole.
Politics vary noticeably by block within 77420. The southeast side is the most Republican-leaning (R+69) and the southwest side is the least Republican-leaning (R+43), a spread of about 25 points.
Why 77420 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 77420, not a ranked or complete list of what matters most.
Areas with low college attainment vote Republican. About 16% of adults in 77420 hold a bachelor's degree, about 9 points below the Texas average of 26%.
Walkability and Republican lean
Places with a low walkability score tend to lean Republican; 77420, TX sits in the bottom quarter nationally on this measure. A walkable street grid does not change how people vote; it mostly reflects how urban a place is.
Why turnout in 77420 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 77420 is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. 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 Texas Secretary of State, Elections Division, 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.