Here are five Republican Senate primaries that could help define the upper chamber in the 2025 session and beyond. The primaries will take place June 4, 2024.

District 3

(Brown County)

There’s a generational battle brewing in Aberdeen, where 70-year-old retired businessman Carl Perry is looking to shift from the House to Senate.

Perry served three terms in Pierre and now seeks the Senate seat formerly held by political ally Al Norvstrup, who is term-limited and toggling back to the House.

Seeking to break the cycle is Katie Washnok, president of Aberdeen Chamber of Commerce Board of Directors and chairman of the Brown County Republicans.

Washnok, who owns a motorcycle customization business with her husband, is taking the business-friendly and “fresh ideas” lane against Perry, who embraced landowner rights against carbon pipeline projects during the 2024 session.

Washnok has cited finding new water sources for the Aberdeen community as her top priority.

She’s well-connected in GOP circles and speaks from the perspective of a young woman raising a family. Perry keeps a high profile at Aberdeen events and might have the edge with older voters, but he’ll have to run on his record in Pierre.

District 4

(Clark, Codington, Deuel, Grant, Hamlin and Roberts counties) 

Nowhere is the trend of establishment vs. far right more pronounced than in this district of rural counties surrounding Watertown, where longtime state Rep. Fred Deutch is running for Senate.

He seeks the seat formerly held by Wiik, the state GOP chair, who was elected in 2016 and is term-limited.

Deutsch, a retired chiropractor, has built a political profile around anti-transgender legislation such as the bathroom bill of 2016 that aimed to bar trans students from using school restrooms that don't match their biological sex.

The proposed legislation made national headlines and was vetoed by then-Gov. Dennis Daugaard.

Deutsch also sought unsuccessfully in 2020 to make it a felony for medical professionals to provide transgender health care to minors, clashing with much of the South Dakota medical community. A separate measure restricting gender-affirming care for minors passed in 2023.

His opponent is Stephanie Sauder, a longtime educator and former mayor of Bryant who was elected to the House in 2022. Sauder has the support of Gov. Kristi Noem, who has talked publicly about being babysat by Sauder as a farm kid in Castlewood.

Noem’s daughter, Kassidy, as well as Crabtree and House Speaker Hugh Bartels were part of a November 2023 fundraiser for Sauder at the home of Schoenbeck, crystallizing the candidate's establishment credentials.

District 16

(Lincoln, Turner and Union counties)

This is another case of a conservative legislator getting term-limited from the House and seeking new horizons in the Senate, potentially changing the makeup of the chamber.

The candidate is Kevin Jensen, a former House majority whip who unsuccessfully challenged Wiik for Republican party chair last year. The former Canton School Board member and "lifetime member" of the National Rifle Association also supported primary challenges to Noem and Schoenbeck in 2022.

Jensen has opposed plans to build a state men’s prison in rural Lincoln County and also criticized pipeline projects using eminent domain for carbon capture. He received a score of 74% from the Greater Sioux Falls Chamber of Commerce on support of business-related bills in 2023, compared to 100% for Bolin.

Jensen faces a stiff challenge for the seat that Bolin held as part of his 16 years as a legislator. The sprawling district map includes Canton, Lennox and Beresford and stretches westward to Marion, offering a contrast in constituencies.

Jensen’s opponent, Eric Hohman, is a fixture in the Canton community, where he was publisher of the Sioux Valley News and served on the school board and community foundation. He manages credit services at First Premier Bank and is expected to have the financial support needed for a competitive race.

District 25

(Minnehaha and Moody counties)

Political campaigns are made by seizing the moment. For Jordan Youngberg, a former state senator looking for a return to Pierre, this district north of Sioux Falls that includes Dell Rapids, Flandreau and Garretson represented an opportunity.

Youngberg, a Dell Rapids native who now lives with his family in Colman, previously served District 8, which includes Lake, Miner, Moody and Sanborn counties. He rose to Senate majority whip but resigned in 2020, after which Noem appointed Crabtree to fill the seat.

Youngberg is challenging District 25 incumbent Tom Pischke, whose voting record makes him one of the most conservative members of the Legislature, according to Citizens of Liberty, a Rapid City-based organization that supports limited government.

The group gave Pischke a 2023 voting approval mark of 90.5%, second among all senators behind Julie Frye-Mueller of Rapid City. The Greater Sioux Falls Chamber of Commerce gave Pischke a score of 56% on business-related bills, last among Sioux Falls-area senators.

Pischke made headlines for his defense of Frye-Mueller, his seatmate in Pierre, when she was censured by the Senate in February 2023 for workplace harassment involving a Legislative Research Council staffer. The staffer said Frye-Mueller harshly criticized the staffer's decision to have her baby vaccinated, saying the baby could "get Down syndrome or autism" or even die.

Pischke threatened to file a criminal complaint against Schoenbeck and the other 26 senators who initially voted to suspend Frye-Muller, but Hughes County prosecutors declined to take the case.

District 30

(Custer, Fall River and Pennington counties)

Frye-Mueller has represented one of South Dakota’s most conservative districts since 2016, when she entered the House along with fellow Republican Tim Goodwin.

She switched over to the Senate in 2020 and survived a tough primary against Goodwin in 2022 to stay there, trumpeting election reform, landowner rights and anti-vaccine legislation.

She holds a perfect rating from Citizens of Liberty, the Rapid City-based libertarian organization for which her husband serves as an unpaid lobbyist. That runs counter to her score of 42% on business-related bills in 2023 from Elevate Rapid City, a contrast that could rise to the surface this primary season.

Frye-Mueller is facing challenges from Republicans Forrest Foster and Amber Hulse, with Hulse drawing much of the attention so far. She’s a former Miss South Dakota who interned at the White House during the Trump administration and has a law degree from Georgetown University.

Hulse, a Hot Springs native who also clerked for Noem when she was the state's U.S. Representative, talked about “fresh leadership” in announcing her candidacy in December 2023.

There’s no secret among moderate Republicans that turning down the drama surrounding Frye-Mueller would be welcomed. Whether the voters in District 30 agree could be a sign of where the Senate is headed for the next two years.

This story was produced by South Dakota News Watch, an independent, nonprofit news organization. Read more in-depth stories at sdnewswatch.org and sign up for an email every few days to get stories as soon as they're published. Contact Stu Whitney at  at stu.whitney@sdnewswatch.org