Thermalito leans Republican by roughly 24 points: about 38% of voters vote Democratic and 62% Republican.
About 47% of adults in Thermalito typically vote, below the U.S. average of about 62%. Among adults in Thermalito, ~18% vote Democratic, ~29% Republican, and ~53% don't vote. The map below shows estimated turnout by block group.
How Thermalito compares
Among cities within 25 miles, Thermalito leans more Republican than 16 of 44 neighbors.
Thermalito runs about 45 points more Republican than California as a whole. California leans Democratic overall, while Thermalito is one of the few Republican-leaning pockets.
Politics vary noticeably by neighborhood within Thermalito. The northwest side is the most Republican-leaning (R+35) and the east side is the least Republican-leaning (R+22), a spread of about 13 points.
Why Thermalito 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 Thermalito, not a ranked or complete list of what matters most.
Thermalito votes Republican even though it is densely developed (about 47%, modestly below the California average of 58%). State and regional patterns outweigh the Democratic lean that density usually predicts here. Low college attainment predicts Republican voting, and Thermalito sits in the bottom quarter (about 13%, below 86% of cities). Thermalito runs against the grain of California, a Republican-leaning pocket in a Democratic-leaning state.
Cancer-screening access and voter turnout
Places with low colon-cancer-screening access tend to turn out at a lower rate; Thermalito, CA 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 Thermalito looks the way it does
Areas with high food insecurity turn out at lower rates. About 23% of adults in Thermalito report food insecurity, about 7 points above the U.S. average of 16%. Renters vote less often than owners, and about 29% of households in Thermalito rent, above 82% of cities. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- South Oroville, CA R+13
- Oroville, CA R+21
- Honcut, CA R+41
- Oroville East, CA R+29
- Palermo, CA R+34
- Oregon City, CA R+41
- Biggs, CA R+49
- Nelson, CA R+36
- Robinsons Corner, CA R+46
- Butte Valley, CA R+25
Cities with Similar Populations
- Thornville, OH R+47
- Woodbury, TN R+68
- Caribou, ME R+21
- Fort Belvoir, VA D+21
- Sturgis, SD R+42
- Bath, MI R+4
- Forest Hill, MD R+33
- Campbell, OH D+19
- Hartford City, IN R+45
- Tylertown, MS R+21
Sources and methodology
Precinct-level voting records used to fit the model come from California Secretary of State, Elections, 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.