National and state Republicans are once again setting their sights on flipping Minnesota's Second District — the state's lone remaining swing seat in Congress — but a contentious intraparty battle for the GOP nomination could stretch on into the summer.

Republican candidate and former federal prosecutor Joe Teirab announced to activists over the weekend that he plans to continue his campaign into the August primary election, regardless of what happens at the congressional district's GOP endorsing convention scheduled for Saturday.

His opponent, conservative attorney Tayler Rahm, is criticizing Teirab for breaking an earlier pledge to abide by the decision of party activists and said he's making the decision because he was already going to lose the party's endorsement. He asked delegates to remember "who is committed to honesty and integrity."

Rahm could be poised to secure the party's endorsement over the weekend, but he's trailing far behind Teirab in fundraising if the contest shifts to a broader set of primary voters. Teirab recently reported ending March with $662,000 in the bank, while Rahm has $59,500 on hand.

"I can only do the right thing; in my view it would not be the right thing to hand Angie Craig an easy victory," Teirab, who is still seeking the endorsement, said in an interview Monday, referring to the incumbent DFL congresswoman. "Sometimes it does boil down to: Can you get your message out there? Will anyone recognize your name? We are in a position to be able to do that."

The outcome of the race is critical for Republicans, who are fighting this fall to maintain their narrow control of the U.S. House. The Second District, represented since 2018 by Craig, is one of a few remaining swing districts in the country that offer them a chance for a pick-up. Some Republicans are worried a potential primary battle will give them a disadvantage in the race.

"A primary challenge, regardless of outcome, will weaken our chances to beat Craig," said Joseph Ditto, the Second District Republican party chair. "We need to be focused on exposing Craig's voting record and how it's hurting people in CD2. We need to start that on April 28, not August 14."

Ditto said the party intends to endorse a candidate on Saturday and hopes both candidates will ultimately decide to abide by pledges they submitted to the party in writing. But the race has bitterly divided some state and national Republicans over who's best to take on Craig in the district, which covers suburban and rural cities south of the Twin Cities.

Both Republicans have been campaigning on the party's top issues this fall: lowering taxes, cutting federal spending and securing the southern border. And while they're both first-time candidates, Rahm is positioning himself as the outsider in the race.

He grew up in Savage and now lives in Burnsville and runs his own law practice based in Minnetonka. Rahm endorsed former President Donald Trump early in the race and pressed his opponent to do the same.

"I'm not going to represent the status quo; the status quo is not working for the American people," he said. "It's time for new leaders to get out there and grassroots candidates to step up."

Teirab, who also lives in Burnsville and grew up in southwest Minnesota, is the son of an immigrant and served in the Marine Corps for five years after law school. He most recently worked as a prosecutor in the U.S. Attorney's Office.

He sees that experience as a key distinction between himself and Rahm. Teirab cited his work as a prosecutor in the Feeding our Future fraud case and prosecuting criminal cases. In his decision to go to the primary, Teirab said a recent Fox News story reported that Rahm scrubbed information from his law firm's website to "downplay the types of criminals he's represented."

"My life's mission is to put bad guys behind bars and help law enforcement do that," Teirab said.

Rahm said Teirab is using baseless "smear tactics" to justify his decision to go on to the primary election.

"As a defense lawyer, I've upheld the highest ethical standards, earning respect from both prosecutors and judges. His attempts to twist the truth won't go unnoticed," Rahm said, adding: "America is exhausted with fast-talking, self-serving bureaucrats who are just another 'yes' vote for special interests."

Former Republican leaders in the district and others have backed Rahm, while former Second District GOP Rep. John Kline and U.S. House Republican Conference Chair Elise Stefanik are among those who are lining up behind Teirab.

Cook Political Report recently shifted its rating in the Second District from likely Democrat to lean Democrat. Craig has fended off GOP challenges the last two election cycles and recently reported having $2.8 million cash on hand heading into the fall election.

DFL Party Chair Ken Martin described the battle between Rahm and Teirab as a "divisive primary between two MAGA extremists." "While Tayler Rahm and Joe Teirab are mired in a race to the bottom, Angie will be talking to voters across the district about the issues that matter most to them."

Craig is an incumbent with high name recognition, and a generic House ballot is about evenly split, said St. Olaf College political science professor Dan Hofrenning. A drawn-out battle on the GOP side could make things harder for Republicans this fall.

"Clearly, it's not going to help increase their chances of winning," he said. "Especially in a presidential year when there's going to be a 50-50 race at the top of the ticket, so no one is going to get an advantage."