Aberdeen businessman Toby Doeden led the South Dakota Republican governor primary with 31% of the vote, advancing to a July 28 runoff alongside incumbent Gov. Larry Rhoden at 25%. Kalshi favorite Dusty Johnson finished third at 23% and is out of the race.
The result reshuffled the November betting picture. Doeden was an outsider candidate who self-funded $4 million and ran on a Make America Healthy Again message. He has never held elected office.
Sen. Mike Rounds won the Republican Senate primary easily and advances to November. Trump-endorsed Attorney General Marty Jackley won the at-large House primary. Both of these races are unlikely to be close.
Democrat Rob Sand will now wait to see which Republican emerges from the July 28 runoff. Kalshi had already priced Democrats as favorites in the governor’s race at 64%, and the chaotic primary may only reinforce that advantage.
South Dakota’s governor’s race is shaping up as one of the more unusual election odds stories of the 2026 cycle. A deep-red state has a fractured Republican Party and a Democratic candidate who has proven he can win statewide.

South Dakota 2026 Primary Recap: Johnson Is Out, Doeden Leads Runoff

PIERRE, S.D. — The prediction markets had it wrong.

Kalshi had Dusty Johnson at 48% to win the South Dakota Republican governor primary heading into Tuesday. Johnson finished third. He will not be on the July 28 runoff ballot. The governor’s race that traders thought was set has completely scrambled the election odds in South Dakota.

Businessman Toby Doeden finished first with 31% of the vote. Incumbent Gov. Larry Rhoden finished second at 25%. Johnson fell to third with 23%, and state House Speaker Jon Hansen came in fourth with 21%.

Election laws in South Dakota require candidates to get 35% or more to win the nomination outright. No one got there. Doeden and Rhoden will meet in a runoff on July 28. The winner faces Democrat Dan Ahlers in November.

Doeden’s Rise: A $4 Million Outsider Campaign That Worked

A year ago, Doeden barely registered in polls. He was at 4% in a Mason-Dixon survey from October 2025. He self-funded $4 million and ran on a Make America Healthy Again platform, attacking both Johnson and Rhoden over legislation that raised sales taxes.

The surge was rapid. He jumped from 18% to 26% in the Emerson College poll between March and May. By election day, Kalshi had moved him to 43% to win the nomination — just five points behind Johnson.

His message connected with older Republican voters who were frustrated with the establishment. On election night in Sioux Falls, Doeden told supporters they were proving the doubters wrong. "Clearly we’re in a very good, strong position," he said.

What Doeden vs. Rhoden Means for the General Election Odds

Before the primary, gubernatorial odds gave Democrats a 64% chance of winning the governor’s race in November. Polymarket had it even higher at 67%. Both numbers were built around the idea that the Republican nominee would be a well-known, credible candidate.

Doeden has never held elected office. Rhoden has a 26% approval rating and lost his first test against three competitors. Neither is the strongest possible general election candidate heading into November.

Democratic state Auditor Rob Sand ran unopposed in Tuesday’s primary. He is the only Democrat to hold statewide office in South Dakota. He won reelection in 2022 even as Republicans swept every other statewide race. His general election odds could actually improve after Tuesday’s result, given that his eventual opponent will be either a first-time candidate or a deeply unpopular incumbent.

Trump won South Dakota by about 29 points in 2024. That structural lean still heavily favors Republicans. But the fractured primary and the weakness of both runoff candidates gives Democrats a real opening in a state they would rarely expect to be competitive.

Senate and House: Rounds and Jackley Win as Expected

The Senate and House primaries went smoothly for Trump-aligned Republicans.

Sen. Mike Rounds won the Republican Senate primary over Justin McNeal and advances to a general election against Democrat Julian Beaudion and Independent Brian Bengs. In an April Mason-Dixon poll, Rounds led McNeal 66% to 18%. He was at 99% on Kalshi to win the nomination. Neither the Senate nor House race is expected to be competitive in November.

State Attorney General Marty Jackley won the at-large U.S. House primary with Trump’s backing. He advances to the general election and is a heavy favorite to hold the seat. No Democrat in South Dakota has won a federal position election since 2008.

The Bottom Line

South Dakota’s primary delivered a genuine upset. Johnson was the market favorite and he finished third. Doeden, a political newcomer, leads the runoff. Rhoden, a deeply unpopular incumbent, somehow survived to fight another day.

The election odds in the governor’s race were already tilted toward Rob Sand before Tuesday. After what happened in the Republican primary, the case for Sand may only get stronger. Watch the July 28 runoff closely.

For anyone tracking the 2026 map, South Dakota’s governor’s race just went from “somewhat interesting” to genuinely unpredictable.

The South Dakota Republican governor runoff is July 28, 2026. The general election in South Dakota is on November 3, 2026.

John Claudette

John spent over three decades as a political analyst and campaign strategist before turning to writing full-time. Having witnessed firsthand the shifting tides of American politics from the local precinct level to the national stage, he brings a seasoned perspective to electoral forecasting and odds analysis. Now, he channels that hard-won experience into accessible, data-driven commentary that cuts through the noise of the 24-hour news cycle. When he's not crunching polling data, he can be found on the golf course — still convinced every putt is a sure thing.