78748 leans heavily Democratic by roughly 38 points: about 69% of voters vote Democratic and 31% Republican.
About 68% of adults in 78748 typically vote, above the U.S. average of about 62%. Among adults in 78748, ~47% vote Democratic, ~21% Republican, and ~32% don't vote. The map below shows estimated turnout by block group.
How 78748 compares
Among zip codes within 15 miles, 78748 leans more Democratic than 18 of 37 neighbors.
78748 runs about 53 points more Democratic than Texas as a whole. Texas leans Republican overall, while 78748 is one of the few Democratic-leaning pockets.
Politics vary noticeably by block within 78748. The east side is the most Democratic-leaning (D+48) and the west side is the least Democratic-leaning (D+20), a spread of about 28 points.
Why 78748 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 78748, not a ranked or complete list of what matters most.
Areas with high college attainment vote Democratic. About 55% of adults in 78748 hold a bachelor's degree, about 27 points above the U.S. average of 28%. Dense areas vote Democratic, and 78748 sits in the top fifth on density (about 85%, above 85% of zip codes). 78748 runs against the grain of Texas, a Democratic-leaning pocket in a Republican-leaning state.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; 78748, TX sits in the top quarter 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 78748 looks the way it does
Areas with high high-school completion turn out at higher rates. About 96% of adults in 78748 have completed high school, about 10 points above the Texas average of 86%. Limited routine healthcare access lines up with lower turnout, and 78748 sits in the bottom quarter on routine-care measures. 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.