Rosemead leans Democratic by roughly 16 points: about 58% of voters vote Democratic and 42% Republican.
About 38% of adults in Rosemead typically vote, below the U.S. average of about 62%. Among adults in Rosemead, ~22% vote Democratic, ~16% Republican, and ~62% don't vote. The map below shows estimated turnout by block group.
How Rosemead compares
Among cities within 25 miles, Rosemead leans more Democratic than 47 of 140 neighbors.
Politically, Rosemead sits close to the rest of California.
Politics vary noticeably by neighborhood within Rosemead. The south side is the most Democratic-leaning (D+25) and the north side is the least Democratic-leaning (D+12), a spread of about 13 points.
Why Rosemead 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 Rosemead, not a ranked or complete list of what matters most.
Dense areas vote Democratic. More than 99% of residents in Rosemead live in densely developed areas, about 64 points above the U.S. average of 36%. A high never-married share predicts Democratic voting, and about 36% of adults in Rosemead have never been married, above 89% of cities.
Paved land cover and Democratic lean
Places with extensive paved surfaces tend to lean Democratic; Rosemead, CA 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 Rosemead looks the way it does
Areas with limited routine healthcare access turn out at lower rates. Rosemead is in the bottom quarter nationally for routine-care measures such as insurance coverage, preventive screenings, and dental visits. Renters vote less often than owners, and about 52% of households in Rosemead rent, about 27 points above the U.S. average of 25%. High food insecurity lines up with lower turnout, and about 27% of adults in Rosemead report food insecurity, above 93% of cities. Learn more about the findings and methodology on the political spectrum map.
Nearby Cities
- San Gabriel, CA D+19
- South El Monte, CA D+28
- Monterey Park, CA D+21
- Temple City, CA D+13
- Alhambra, CA D+28
- El Monte, CA D+26
- Montebello, CA D+28
- San Marino, CA D+21
- South Pasadena, CA D+52
- Arcadia, CA D+14
Cities with Similar Populations
- Elyria, OH D+2
- Danville, CA D+27
- Pocatello, ID R+18
- Lakeville, MN Even
- Florence, AL R+34
- Panama City, FL R+31
- Ormond Beach, FL R+24
- Coconut Creek, FL D+9
- Fountain Valley, CA R+3
- Bentonville, AR R+14
All Local Stats
Home Services
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.