Why It Matters
South Dakota is holding its first statewide runoff election for a major party nomination since a 1985 law took effect, marking a historic shift in how the state selects its Republican gubernatorial nominee. The winner will face Democrat Dan Ahlers, a former legislator, in the November general election.
What Happened
Registered Republicans across South Dakota voted today in a runoff between Governor Larry Rhoden and Aberdeen businessman Toby Doeden, the top two finishers in the June 2 primary. No candidate reached the 35 percent threshold required to win outright—a requirement established in 1985 that had never before forced a statewide gubernatorial runoff.
Polls opened at 7 a.m. and remained open until 7 p.m. local time. Only registered Republicans could participate in the election, which featured no other items on the ballot. Registration had closed July 13.
The race emerged after Governor Kristi Noem resigned in January 2025 to join President Donald Trump’s administration. Rhoden, her lieutenant governor, was automatically promoted to the governor’s office. House Speaker Jon Hansen announced his candidacy April 24, 2025, followed by Doeden, U.S. Representative Dusty Johnson, and Rhoden in subsequent months. Johnson, who served four terms in Congress, finished third in the primary.
By the Numbers
31% — Doeden’s share of the June 2 primary vote
25% — Rhoden’s primary result
23% — Johnson’s primary share
21% — Hansen’s primary result
43% — Republican primary turnout across the state
24,502 — advance ballots cast in the runoff by Monday morning
26,125 — advance Republican ballots cast during the June primary
330,000 — total registered Republicans in South Dakota
Zoom Out
The 1985 law requiring a runoff when no candidate clears 35 percent was designed to ensure the party nominee has broader support than a plurality might indicate. Before that law, state party convention delegates selected nominees in contested situations. South Dakota’s approach mirrors runoff systems used in other states, though most rely on runoffs in general elections rather than primary contests.
What’s Next
The runoff winner will advance to the November 3 general election as the Republican nominee, facing Ahlers. Advance voting had been available since June 12.