For most of its history, San Joaquin County has been a Republican-leaning swing county, voting for the national winner in all but 4 presidential elections (1884, 1948, 1960, 1976) from 1880 to 2012. In 2016, Hillary Clinton became the first Democratic Party candidate who lost nationally to win the county, and she did so by a sizable margin of around 14 points. On the other hand Donald Trump, posted the worst result in the county in history by a national Republican Party electoral college winner, being held to under 40% of the vote.