San Mateo County, California
Latest: 2024
Safe Democratic — shifted 7.4pp toward Republicans in 2024 — 40 presidential elections on record
Race & ancestry
| Group | % |
|---|---|
▶White (Non-Hispanic)(13) | 34.7% |
▶Hispanic / Latino(20) | 24.9% |
▶Black / African American(11) | 2.1% |
▶Asian(6) | 31.4% |
▶Middle Eastern / North African(11) | 2.2% |
▶Native American / Alaska Native(4) | 1.1% |
▶Native Hawaiian / Pacific Islander(5) | 1.1% |
Multiracial / Other | 4.6% |
Religious adherence
| Tradition | % Pop | % Adherents |
|---|---|---|
| Catholic | 21.1% | 62.8% |
| Other | 5.8% | 17.2% |
| Evangelical Protestant | 3.5% | 10.4% |
| Mainline Protestant | 1.8% | 5.4% |
| LDS (Mormon) | 1.8% | 5.4% |
| Orthodox Christian | 0.9% | 2.8% |
| Black Protestant | 0.5% | 1.3% |
| Non-religious | 66.3% | — |
Presidential results
| Year | Result |
|---|---|
| 2024 | Harris+50.3 |
| 2020 | Biden+57.7 |
| 2016 | Clinton+57.2 |
| 2012 | Obama+46.7 |
| 2008 | Obama+48.7 |
| 2004 | Kerry+40.2 |
| 2000 | Gore+33.3 |
| 1996 | Clinton+31.3 |
| 1992 | Clinton+26.8 |
San Mateo, California is a county that has a population of 742,340. In the 2024 presidential election, it voted Democratic with a margin of D+50.3. Akashic Edge tracks 40 presidential elections here, dating back to 1868.
| Year | Dem % | Rep % | Margin | Swing |
|---|---|---|---|---|
| 2024 | 73.5% | 23.2% | D+50.3 | R+7.4 |
| 2020 | 77.9% | 20.2% | D+57.7 | D+0.4 |
| 2016 | 75.7% | 18.4% | D+57.2 | D+10.6 |
| 2012 | 72.1% | 25.5% | D+46.7 | R+2.1 |
| 2008 | 73.5% | 24.7% | D+48.7 | D+8.5 |
| 2004 | 69.5% | 29.2% | D+40.2 | D+6.9 |
| 2000 | 64.3% | 31.0% | D+33.3 | D+2.0 |
| 1996 | 60.6% | 29.2% | D+31.3 | D+4.5 |
| 1992 | 54.0% | 27.2% | D+26.8 | D+14.0 |
| 1988 | 55.7% | 42.9% | D+12.8 | D+17.8 |
| 1984 | 46.9% | 51.9% | R+5.0 | D+7.3 |
| 1980 | 36.6% | 48.8% | R+12.2 | R+6.0 |
| 1976 | 44.4% | 50.6% | R+6.2 | D+3.8 |
| 1972 | 42.8% | 52.8% | R+10.0 | R+13.5 |
| 1968 | 47.2% | 43.7% | D+3.5 | R+25.3 |
| 1964 | 64.3% | 35.5% | D+28.8 | D+32.4 |
| 1960 | 48.0% | 51.7% | R+3.7 | D+18.5 |
| 1956 | 38.8% | 61.0% | R+22.2 | D+4.3 |
| 1952 | 36.5% | 63.0% | R+26.6 | R+9.5 |
| 1948 | 39.7% | 56.7% | R+17.0 | — |
What defines San Mateo?
It has a diverse, highly educated electorate — the core of the modern Democratic coalition.
County in State Context
Ask the Historian
Explore this county's political evolution with the Historian
Key Insights
High-confidence patterns distilled from this geography's election history.
- Has voted Democratic in the last 5 presidential elections
- Latest election (2024) was a Democratic landslide with a 50.3% margin
- College attainment is 54% — 21pp above the national average. Similar education levels correlate with Democratic lean nationally
Located In
San Mateo sits inside these higher-level geographies.