- South Dakota holds its primary today, June 2. The Republican governor’s race is the most volatile in the state — four candidates are fighting for the nomination with no clear frontrunner heading into Election Day.
- Kalshi prices U.S. Rep. Dusty Johnson as the narrow favorite at 48% to win the GOP governor primary, with businessman Toby Doeden surging to 43%. A runoff on July 28 is widely expected, as no candidate is likely to clear the 35% threshold needed to win outright.
- Sen. Mike Rounds is seeking a third term and sits at 99% on Kalshi to win the GOP nomination. The general election is not competitive. South Dakota has not elected a Democrat to federal office since 2008.
- State Attorney General Marty Jackley is the Republican nominee for South Dakota’s at-large House seat and sits at 99% on Kalshi. The race is not expected to be competitive in November.
- The real election odds story in South Dakota is in the governor’s primary — a chaotic four-way race that may not produce a winner tonight and has already produced accusations of blackmail between two of the candidates.
PIERRE, S.D. — South Dakota voters are casting ballots today in one of the most unpredictable primaries in the state in decades. Polls close at 7 p.m. Central time.
The governor’s race is the main event. Four Republicans are competing for a nomination that no one is favored to win outright. And if tonight’s results are as close as the polls suggest, the state will be doing this again on July 28.
The Senate and House races are settled terrain for Republicans. But the governor’s primary is genuinely wide open, and the prediction markets with election odds in South Dakota know it.
Governor: Four Candidates, One of the Messiest Primaries in the State’s History
Incumbent Gov. Larry Rhoden succeeded Kristi Noem in January 2025 after she resigned to become secretary of homeland security under President Donald Trump. But Rhoden is not being treated like an incumbent.
Three credible challengers have been fighting him all cycle: U.S. Rep. Dusty Johnson, state House Speaker Jon Hansen, and Aberdeen businessman Toby Doeden. South Dakota Searchlight’s editor-in-chief described the race plainly: people are treating it as an open seat.
Under South Dakota law, a candidate needs at least 35% to win the primary outright. If no one hits that mark tonight, the top two finishers will advance to a runoff election on July 28.
Where the Prediction Markets Stand Right Now
Kalshi has Johnson at 48% to win the Republican nomination, with Doeden right behind at 43%. Rhoden is at 14%, and Hansen sits at 4%.
That 48-43 split between Johnson and Doeden tells you everything: traders think one of those two will win, but they are not willing to bet heavily on either one. The gubernatorial odds market is essentially pricing a coin flip between the two frontrunners.
Averaging the three public polls released this month, Rhoden is at 25%, Doeden at 24%, and Johnson at 23%, with Hansen at 17%. That polling spread, combined with South Dakota’s 35% threshold rule, makes a July runoff the most likely outcome.
Dusty Johnson — 48% on Kalshi
Johnson, 48, is South Dakota’s at-large U.S. Representative and has served in Congress since 2019. He announced his gubernatorial bid in June 2025 and has raised approximately $3.7 million, dwarfing the rest of the field.
He led in most polls throughout the campaign, though his numbers slipped from 28% to 23% in the most recent Emerson survey as Doeden surged. Johnson’s campaign has framed him as a pragmatic problem-solver with a deep executive resume.
The race took a sharp turn in its final days when Rhoden publicly accused Johnson of attempting to persuade him not to enter the gubernatorial race. Johnson has denied the allegation.
Toby Doeden — 43% on Kalshi
Doeden is an Aberdeen businessman and conservative activist who entered the race as a long shot and has surged dramatically in the final weeks. His support jumped from 18% in March to 26% in the latest Emerson poll as anti-establishment energy consolidated around him.
He performs especially well among voters over 70, where he leads the field, and has been self-funding significant portions of his campaign. His rise mirrors the trajectory of outside-money populist candidates in other Republican primaries across the country in 2026.
Rhoden and Hansen — Both Fighting for Relevance
Rhoden entered the race as the default incumbent but never consolidated that advantage. His approval rating is deeply underwater — just 26% in the Emerson survey — and he has been outspent and outpolled all cycle.
Hansen, 36, is the South Dakota House Speaker and has gained ground in late polls, climbing to 17-18% in recent surveys. His small-dollar donor base and conservative credibility give him a path to the runoff, but the window is narrow.
Senate and House: Both Settled Before the Votes Are Counted
Sen. Mike Rounds is seeking a third term. He faces a primary challenge from Justin McNeal, a local candidate with no serious support. The Senate election odds at Kalshi have Rounds at 99% to win the nomination.
The general election is even less of an obstacle. Julian Beaudion is the only Democrat running, and he is unopposed in the Democratic primary. South Dakota has not elected a Democrat to federal office since 2008, when Sen. Tim Johnson and Rep. Stephanie Herseth Sandlin both won reelection.
In the at-large House race, state Attorney General Marty Jackley is the overwhelming Republican favorite. Kalshi prices his house election odds at 99% to win the GOP primary. He faces James Bialota, a nominal challenger. The general election is rated safe Republican.
The Bottom Line
South Dakota’s Senate and House races are not competitive. The general election odds in both contests are overwhelmingly Republican, and nothing tonight is expected to change that.
The governor’s race is the story. Johnson and Doeden are in a near-deadlock on Kalshi. The polls suggest a runoff is the most likely outcome. And even if someone clears 35% tonight, the race has been bruising enough that the winner will head into November with dents.
Democratic nominee Dan Ahlers will be waiting. He is not favored in deep-red South Dakota — but in a cycle where incumbents and establishment candidates have been getting battered, tonight’s result in Pierre is worth watching.
South Dakota’s primary is today, June 2, 2026. The runoff, if needed, will be July 28. The general election is November 3, 2026.
