Although the presidential primaries are all completed, states continue to hold congressional and state-level primaries throughout the summer. On Tuesday, the candidates for one major Senate race will be officially set, and a few potentially vulnerable incumbents will try to fend off primary challengers. 

A crowded GOP primary for Senate in Nevada will come to a close on Tuesday for Republicans seeking to challenge incumbent Sen. Jacky Rosen (D-Nev.). Retired Army Capt. Sam Brown, who unsuccessfully sought the Republican nomination for Senate in 2022, is the front-runner, having secured Trump’s last-minute endorsement on Sunday. 

But he’s facing two major opponents in former U.S. Ambassador to Iceland Jeff Gunter, who served during the Trump administration, and former state Assembly member Jim Marchant, who has been a strong backer of Trump’s false election fraud claims. Both Gunter and Marchant tried to position themselves as more loyal supporters of Trump than Brown, who kept his distance at times throughout the race. 

Meanwhile, Rep. Nancy Mace (R-S.C.) is trying to hold off a primary challenge, including from former state official Catherine Templeton, who has attacked her over various controversies, including allegations of flip-flipping on issues and voting to oust former House Speaker Kevin McCarthy (R-Calif.). She has Trump’s endorsement, but she will need to reach a majority of the vote to avoid a runoff in a three-way race, as The Hill’s Julia Mueller reports. 

And Rep. William Timmons (R-S.C.) is seeking to avoid an upset in his primary against state Rep. Adam Morgan, who is running to his right as a founder of the state House’s Freedom Caucus. Morgan has the support of far-right House members like Reps. Bob Good (R-Va.) and Scott Perry (R-Pa.), but Trump has backed Timmons. 

Elsewhere, two Maine state legislators are opposing each other in a primary to face Rep. Jared Golden (D-Maine), a moderate Democrat representing a district that voted for Trump in 2020. Trump has endorsed state Rep. Austin Theriault, also a former NASCAR driver. 

In North Dakota, Rep. Kelly Armstrong (R) appears to be the favorite to succeed outgoing Gov. Doug Burgum (R), having secured most major endorsements in the state and support from Trump. But he will face Lt. Gov. Tammy Miller (R), who has Burgum’s endorsement.