Zapata County leans slightly Republican by roughly 6 points: about 47% of voters vote Democratic and 53% Republican.
About 56% of adults in Zapata County typically vote, below the U.S. average of about 62%. Among adults in Zapata County, ~26% vote Democratic, ~29% Republican, and ~45% don't vote. The map below shows estimated turnout by block group.
How Zapata County compares
Among counties within 50 miles, Zapata County is the most Republican-leaning.
Zapata County runs about 7 points more Democratic than Texas as a whole.
Politics vary noticeably by city within Zapata County. The north side runs the most Democratic (Even) and the southwest side runs the most Republican (R+17), a spread of about 18 points.
Why Zapata County leans the way it does
This analysis examined 14,881 data points per county to find what predicts political lean and turnout. The items below are a few correlations that stood out for Zapata County, not a ranked or complete list of what matters most.
Areas with low college attainment vote Republican. About 15% of adults in Zapata County hold a bachelor's degree, about 11 points below the Texas average of 26%. Dense places usually vote Democratic, but Zapata County runs against that pattern. A high family-household share predicts Republican voting, and about 74% of households in Zapata County are family households, above 92% of counties.
Cancer-screening access and voter turnout
Places with low colon-cancer-screening access tend to turn out at a lower rate; Zapata County, TX sits in the bottom tenth nationally on this measure. Cancer screening does not drive turnout; it reflects income, insurance, and healthcare access.
Why turnout in Zapata County looks the way it does
Areas with limited routine healthcare access turn out at lower rates. Zapata County 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 37%, about 16 points below the Texas average of 54%. Low high-school completion lines up with lower turnout, and about 66% of adults in Zapata County have completed high school, in the bottom fraction of counties. High-crime urban areas turn out at lower rates, and Zapata County sits in the top 15% on a violent-crime measure. Learn more about the findings and methodology on the political spectrum map.
Nearby Counties
- Starr County, TX R+7
- Webb County, TX Even
- Jim Hogg County, TX R+2
- Brooks County, TX D+7
- Duval County, TX R+10
- Hidalgo County, TX R+2
- Kenedy County, TX R+44
- Jim Wells County, TX R+14
- Kleberg County, TX R+6
- Willacy County, TX R+7
Counties with Similar Populations
- Walthall County, MS R+26
- White County, IL R+59
- Murray County, OK R+59
- Crockett County, TN R+57
- Faribault County, MN R+38
- Madison County, VA R+34
- Ketchikan Gateway Borough, AK R+3
- Newton County, IN R+54
- Lamar County, AL R+77
- Morgan County, OH R+55
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.