San Carlos leans slightly Republican by roughly 12 points: about 44% of voters vote Democratic and 56% Republican.
About 29% of adults in San Carlos typically vote, below the U.S. average of about 62%. Among adults in San Carlos, ~13% vote Democratic, ~16% Republican, and ~71% don't vote. The map below shows estimated turnout by block group.
How San Carlos compares
Among cities within 25 miles, San Carlos leans more Republican than 34 of 43 neighbors.
Politically, San Carlos sits close to the rest of Texas.
Politics vary noticeably by neighborhood within San Carlos. The northeast side is the most split-leaning (R+28) and the southeast side is the least split-leaning (Even), a spread of about 26 points.
Why San Carlos leans the way it does
This analysis examined 14,881 data points per city to find what predicts political lean and turnout. The items below are a few correlations that stood out for San Carlos, not a ranked or complete list of what matters most.
San Carlos votes Republican even though it is densely developed (about 24%, modestly below the Texas average of 35%). State and regional patterns outweigh the Democratic lean that density usually predicts here. Low college attainment predicts Republican voting, and San Carlos sits in the bottom quarter (about 15%, below 77% of cities). A high family-household share predicts Republican voting, and about 83% of households in San Carlos are family households, above 94% of cities.
Preventive-care access and voter turnout
Places with limited routine preventive-care access tend to turn out at a lower rate; San Carlos, 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 San Carlos looks the way it does
Areas with limited routine healthcare access turn out at lower rates. San Carlos 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 36%, about 17 points below the Texas average of 54%. Low high-school completion lines up with lower turnout, and about 66% of adults in San Carlos have completed high school, in the bottom fraction of cities. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Edinburg, TX Even
- Faysville, TX R+13
- Doolittle, TX R+8
- San Manuel-Linn, TX R+13
- Alton, TX R+3
- Cesar Chavez, TX Even
- Nurillo, TX R+5
- Lopezville, TX Even
- Palmhurst, TX R+9
- McAllen, TX R+2
Cities with Similar Populations
- Piedmont, TX R+60
- Swisshome, OR R+19
- Curtis, NY R+47
- Maplesville, KY R+72
- Lumbull, AL R+81
- Elijah, MO R+67
- Kaufman, IL R+44
- Piney Grove, AR R+37
- Dairy, OR R+55
- Kelly, TX R+45
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.