San Juan is a true toss-up. About 51% of voters here vote Democratic and 49% Republican.
About 38% of adults in San Juan typically vote, below the U.S. average of about 62%. Among adults in San Juan, ~20% vote Democratic, ~19% Republican, and ~61% don't vote. The map below shows estimated turnout by block group.
How San Juan compares
Among cities within 25 miles, San Juan sits roughly in the middle of the political spectrum, with 50 neighbors leaning further in the place's direction and 1 leaning the other way.
San Juan runs about 15 points more Democratic than Texas as a whole. Texas leans Republican overall, while San Juan sits closer to the political middle.
Politics vary noticeably by neighborhood within San Juan. The west side runs the most Democratic (D+10) and the southeast side runs the most Republican (R+4), a spread of about 14 points.
Why San Juan 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 Juan, not a ranked or complete list of what matters most.
San Juan votes against the grain of Texas. Texas leans Republican overall, while San Juan runs about 15 points more Democratic.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; San Juan, TX sits in the top tenth 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 San Juan looks the way it does
Areas with limited routine healthcare access turn out at lower rates. San Juan 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 42%, about 11 points below the Texas average of 54%. Low high-school completion lines up with lower turnout, and about 63% of adults in San Juan have completed high school, in the bottom fraction of cities. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- Alamo, TX R+3
- Pharr, TX Even
- Lopezville, TX Even
- McAllen, TX R+2
- Donna, TX Even
- Muniz, TX R+5
- Cesar Chavez, TX Even
- Nurillo, TX R+5
- El Gato, TX R+16
- Edinburg, TX Even
Cities with Similar Populations
- Belton, TX R+32
- Long Beach, NY D+5
- Copperas Cove, TX R+22
- Cullman, AL R+71
- Kearney, NE R+29
- Peachtree City, GA R+18
- Fairborn, OH R+11
- Ocean Springs, MS R+48
- Bangor, ME D+13
- South Salt Lake, UT D+38
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.