- Source: 1912 South Dakota gubernatorial election
- 1912 South Dakota gubernatorial election
- 2018 South Dakota gubernatorial election
- 2022 South Dakota gubernatorial election
- 1998 South Dakota gubernatorial election
- 2026 South Dakota gubernatorial election
- 2006 South Dakota gubernatorial election
- 1994 South Dakota gubernatorial election
- 1974 South Dakota gubernatorial election
- 2014 South Dakota gubernatorial election
- 1986 South Dakota gubernatorial election
The 1912 South Dakota gubernatorial election was held on November 5, 1912. Incumbent Republican Governor Robert S. Vessey declined to run for re-election to a third term. Lieutenant Governor Frank M. Byrne won the Republican primary to succeed Vessey, and then faced State Senator Edwin S. Johnson, the Democratic nominee, in the general election. Byrne only narrowly defeated Johnson, winning just 49% of the vote to Johnson's 46%, the closest gubernatorial election since 1898.
Primary elections
Primary elections were held on June 4, 1912.
= Democratic primary
=Candidates
Edwin S. Johnson, former State Senator
P. F. Wickhem, former State Senator
Results
= Republican primary
=Candidates
Frank M. Byrne, Lieutenant Governor of South Dakota
George W. Egan, disbarred attorney, 1910 Republican candidate for Governor
Loomis S. Cull, Registrar of the Rapid City United States Land Office
Results
= Prohibition primary
=Candidates
O. W. Butterfield, Prohibition candidate for Governor in 1910
Results
= Socialist primary
=Candidates
Samuel Lovett
Results
General election
= Candidates
=Edwin S. Johnson, Democratic
Frank M. Byrne, Republican
O. W. Butterfield, Prohibition
Samuel Lovett, Socialist