East San Mateo leans heavily Democratic by roughly 40 points: about 70% of voters vote Democratic and 30% Republican.
About 50% of adults in East San Mateo typically vote, below the U.S. average of about 62%. Among adults in East San Mateo, ~35% vote Democratic, ~15% Republican, and ~50% don't vote. The map below shows estimated turnout by block group.
How East San Mateo compares
Among neighborhoods within 5 miles, East San Mateo is the least Democratic-leaning.
East San Mateo runs about 20 points more Democratic than California as a whole.
Why East San Mateo leans the way it does
Density, race composition, education, and family structure all sit close to their national averages in East San Mateo. The lean here lands roughly where demographic data alone would predict.
Park access and Democratic lean
Places with heavy park coverage tend to lean Democratic; East San Mateo, San Mateo, CA sits in the top quarter nationally on this measure. Park access does not change how people vote; it tends to track denser, higher-income areas.
Why turnout in East San Mateo looks the way it does
Crowded housing lines up with lower turnout. About 10% of homes in East San Mateo have more than one occupant per room, above 91% of neighborhoods. Low high-school completion lines up with lower turnout, and about 85% of adults in East San Mateo have completed high school, below 77% of neighborhoods. Learn more about the findings and methodology on the political spectrum map.
Nearby Neighborhoods
- Shoreview, San Mateo, CA D+44
- Downtown San Mateo, San Mateo, CA D+55
- Haywood Park, San Mateo, CA D+52
- Baywood-Aragon, San Mateo, CA D+51
- North Central San Francisco, San Mateo, CA D+50
- Marina Lagoon, San Mateo, CA D+50
- Beresford, San Mateo, CA D+52
- Hillsdale, San Mateo, CA D+50
- Downtown Burlingame, Burlingame, CA D+52
- Sugerloaf, San Mateo, CA D+50
Neighborhoods with Similar Populations
- Kelvyn Grove, Chicago, IL D+35
- West Henderson, Henderson, NV Even
- Benton Park, Bakersfield, CA D+6
- West End, Billings, MT R+20
- Bevo Mill, St. Louis, MO D+40
- Southwyck, Toledo, OH D+35
- Wanskuck, Providence, RI D+40
- Sulphur Springs, Tampa, FL D+43
- Downtown Paterson, Paterson, NJ D+32
- Jackson Triangle, Hayward, CA D+38
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.