78634 is a true toss-up. About 50% of voters here vote Democratic and 50% Republican.
About 68% of adults in 78634 typically vote, above the U.S. average of about 62%. Among adults in 78634, ~34% vote Democratic, ~34% Republican, and ~32% don't vote. The map below shows estimated turnout by block group.
How 78634 compares
Among zip codes within 15 miles, 78634 sits roughly in the middle of the political spectrum, with 5 neighbors leaning further in the place's direction and 13 leaning the other way.
78634 runs about 14 points more Democratic than Texas as a whole. Texas leans Republican overall, while 78634 sits closer to the political middle.
Politics vary noticeably by block within 78634. The west side runs the most Democratic (D+9) and the northeast side runs the most Republican (R+19), a spread of about 28 points.
Why 78634 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 78634, not a ranked or complete list of what matters most.
78634 votes against the grain of Texas. Texas leans Republican overall, while 78634 runs about 14 points more Democratic.
Developed land and Democratic lean
Places with a heavily developed built environment tend to lean Democratic; 78634, TX sits in the top quarter nationally on this measure. Developed land does not change how people vote; it mostly reflects how urban a place is.
Why turnout in 78634 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 78634 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.