South Dakota voters are choosing between Gov. Larry Rhoden and three prominent Republican challengers on Tuesday in a governor’s primary that could end tonight — or stretch into a June 23 runoff. Rhoden, who took over the office in early 2025 after Kristi Noem left for President Donald Trump’s Cabinet, is seeking a full term while U.S. Rep. Dusty Johnson, state House Speaker Jon Hansen and businessman Toby Doeden try to stop him.
The race matters because South Dakota is one of the most reliably Republican states in the country, and the GOP nominee is likely to start the general election with a clear advantage. Voters in the primary also have a hard number to watch: candidates for governor, U.S. Senate and U.S. House must clear 35% to win the nomination outright.
For Doeden, the contest places a businessman in a field packed with officeholders and well-known party figures. Johnson brings the state’s lone House seat, Hansen brings the speakership, and Rhoden brings the governor’s office itself after serving as lieutenant governor under Noem before stepping up when she resigned. The winner will face former state Sen. Dan Ahlers, who is unopposed for the Democratic nomination.
That is where the race gets tricky for Rhoden. An incumbent normally starts with the advantage of the job, but he is still being tested by three Republicans with their own bases, and the 35% threshold means a fractured vote can deny any of them a clean win. If no candidate reaches that mark, the top two finishers move on to a June 23 runoff.
Polls close at 7 p.m. local time in South Dakota, which is 8 p.m. ET in most of the state and 9 p.m. ET in Mountain time counties. When the counting starts, the question is not just who leads, but whether anyone has enough support to avoid another round.
