77566 leans heavily Republican by roughly 36 points: about 32% of voters vote Democratic and 68% Republican.
About 65% of adults in 77566 typically vote, near the U.S. average of about 62%. Among adults in 77566, ~21% vote Democratic, ~44% Republican, and ~35% don't vote. The map below shows estimated turnout by block group.
How 77566 compares
Among zip codes within 15 miles, 77566 leans more Republican than 3 of 6 neighbors.
77566 runs about 23 points more Republican than Texas as a whole.
Politics vary noticeably by block within 77566. The northwest side is the most Republican-leaning (R+54) and the south side is the least Republican-leaning (R+21), a spread of about 33 points.
Why 77566 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 77566, not a ranked or complete list of what matters most.
Car-dependent areas vote Republican. About 83% of residents in 77566 drive to work alone, about 9 points above the U.S. average of 74%.
Population density and Democratic lean
Places with high population density tend to lean Democratic; 77566, TX sits in the top quarter nationally on this measure.
Why turnout in 77566 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 77566 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.