1916 United States Senate election in California

Governor of California and 1912 Progressive Party vice presidential nominee Hiram Johnson won the open seat, defeating Democratic attorney and Mayor of San Marino George Patton.

George Patton was unopposed on the ballot, but Hiram Johnson, Willis Booth, and Walter Thomas Mills received write-in votes.

Hiram Johnson was unopposed on the primary ballot, but Willis Booth did receive write-in votes.

Walter Thomas Mills was unopposed on the primary ballot, but Hiram Johnson and Willis Booth received write-in votes.

Atwood was unopposed on the primary ballot, but Hiram Johnson and Willis Booth received write-in votes.