78155 leans Republican by roughly 28 points: about 36% of voters vote Democratic and 64% Republican.
About 59% of adults in 78155 typically vote, near the U.S. average of about 62%. Among adults in 78155, ~21% vote Democratic, ~38% Republican, and ~41% don't vote. The map below shows estimated turnout by block group.
How 78155 compares
Among zip codes within 15 miles, 78155 leans more Republican than 1 of 4 neighbors.
78155 runs about 15 points more Republican than Texas as a whole.
Politics vary noticeably by block within 78155. The southwest side is the most Republican-leaning (R+52) and the north side is the least Republican-leaning (R+7), a spread of about 45 points.
Why 78155 leans the way it does
Density, race composition, education, and family structure all sit close to their national averages in 78155. The lean here lands roughly where demographic data alone would predict.
High-school completion, uninsured rate, and voter turnout
Places that combine low high-school-completion share and a high uninsured rate tend to turn out at a lower rate, as 78155, TX does.
Why turnout in 78155 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 78155 is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The uninsured rate here is about 21%, about 11 points above the U.S. average of 10%. 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.