77840 leans Democratic by roughly 28 points: about 64% of voters vote Democratic and 36% Republican.
About 37% of adults in 77840 typically vote, below the U.S. average of about 62%. Among adults in 77840, ~24% vote Democratic, ~13% Republican, and ~63% don't vote. The map below shows estimated turnout by block group.
How 77840 compares
Among zip codes within 15 miles, 77840 is the most Democratic-leaning.
77840 runs about 42 points more Democratic than Texas as a whole. Texas leans Republican overall, while 77840 is one of the few Democratic-leaning pockets.
Politics vary noticeably by block within 77840. The northwest side is the most Democratic-leaning (D+34) and the southeast side is the least Democratic-leaning (D+16), a spread of about 18 points.
Why 77840 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 77840, not a ranked or complete list of what matters most.
Dense areas vote Democratic. About 97% of residents in 77840 live in densely developed areas, about 61 points above the U.S. average of 36%. High college attainment predicts Democratic voting, and 77840 sits in the top quarter (about 55%, above 92% of zip codes). A high never-married share predicts Democratic voting, and about 80% of adults in 77840 have never been married, in the top fraction of zip codes.
Preventive-care access and voter turnout
Places with limited routine preventive-care access tend to turn out at a lower rate; 77840, TX sits in the bottom tenth nationally on this measure. Dental visits do not drive turnout; the rate reflects income, insurance, and healthcare access, which line up with who votes.
Why turnout in 77840 looks the way it does
Areas with limited routine healthcare access turn out at lower rates. 77840 is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. The dental-visit rate here is about 44%, about 10 points below the Texas average of 54%. Renters vote less often than owners, and about 92% of households in 77840 rent, compared to around 35% in nearby zip codes. 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.