Wisconsin Republicans want to beat Sen. Tammy Baldwin and hope a messy primary doesn't stop them

Republicans in Wisconsin say they are nervously eyeing whether the party's upcoming Senate primary will remain civil -- or morph into another messy, high-stakes battle.

Conservative strategists and experts who spoke with ABC News warned that how many people end up running -- and how much blood is drawn in their fight for the nomination -- could make a difference in how strongly the party performs in a key swing state when any one Senate race could determine control the chamber and the fate of things like Supreme Court nominations.

"I would hope that they would focus on their positives during the primaries and not run each other down. We've seen that model here in Wisconsin, both in the 2018 U.S. Senate primary and in the 2022 gubernatorial race, and it ultimately hurt the person that won the primary because a lot of Republicans sat on their hands in the general," said Wisconsin GOP strategist Bill McCoshen, referencing past general elections Republicans lost after brutal nominating fights.

There were also protracted Senate primary battles last year in Arizona, Pennsylvania and New Hampshire, where more mainstream and more MAGA candidates fought it out and the Trump-backed choices ultimately prevailed.

Democrats went on to win in each state, underscoring how the Republican base sometimes struggles to pick candidates who can win over the general electorate.

The Wisconsin GOP hasn't yet recruited any major candidate to take on Democratic Sen. Tammy Baldwin, but businessman Eric Hovde is laying the groundwork for a run and Scott Mayer, another businessman, is considering a campaign as well. The potential remains for other hopefuls to announce, too.

Montana Sen. Steve Daines, the chair of Senate Republicans' campaign arm, already said Hovde "is gonna get in that race," and a source familiar with Hovde's thinking told ABC News that a formal announcement would likely come in the early part of 2024.

Mayer, meanwhile, told ABC News that he's met with potential donors like the Uihleins and that while he and Mayer have a cordial relationship, Hovde's decision wouldn't influence his own. (The Uihleins did not respond to a request for comment.)

Outside observers and people familiar with Mayer and Hovde's thinking said they were optimistic that both men wouldn't come out swinging against the other if they face off.

"I don't think anybody wants to have an ugly primary," said one source, who asked not to be quoted by name because of professional relationships in the state. "We haven't had a ton of success recently when it's been a tough primary."

Mayer said, of Hovde: "I don't know that it can ever completely remain civil, but we get along good. And technically we're both on the same team. So, I would have to say that we would be reasonably decent to each other, absolutely."

Hovde, a deep-pocketed banking and real estate entrepreneur who unsuccessfully ran for the Senate in 2012, is expected to have the backing of the National Republican Senatorial Committee, which has been exercising a far more muscular approach to primaries after adopting a largely hands-off strategy in nominating contests in 2022 -- which, experts said, ultimately helped lead to more controversial nominees winning out before losing in the general election.

Democrats, despite President Joe Biden's unpopularity, actually expanded their control of the Senate last year but are defending numerous seats in 2024; Republicans only need to win back -- at most -- two seats.

Mayer, who runs a staffing company and whose personal wealth is also hefty but not thought to be as expansive as Hovde's, told ABC News that he would be willing to invest some of his own money in a campaign, too.

One strategist predicted that if the primary really heats up, it could also become seriously expensive -- "you gotta be ready to spend $20, $30 million."

The hypothetical matchup could mirror other headline-making primaries in 2024, including in West Virginia and potentially in Montana.

However, as Mayer suggested, both he and Hovde may not run for the nomination by seeking to paint the other as a radically different candidate.

Both would be anticipated to highlight the economy given their professional backgrounds and polls showing it's a major concern for voters. They've remained largely tight-lipped on other issues, though Mayer did say in an interview that he supports allowing abortions through the first trimester of pregnancy with exceptions for rape, incest, concerns for the mother's health and fatal fetal abnormalities.

"I'm 100%, unapologetically pro-life. But I also say that I'm doing this to represent the people and if the people want access, at least for a reasonable period of time, I would absolutely do that," he said. "Something like the first trimester is what people are saying they want, and that's what I'd have to get behind and do, period. That's a real easy one for me."

Whomever wins the primary will be facing Baldwin, who has been able to win reelection in the narrowly divided state, at times by yawning margins.

Even Republicans who spoke to ABC News conceded her electoral prowess, praising her policy focus, retail expertise in areas that aren't necessarily friendly to Democrats and a dedicated constituent services department.

"She is extremely organized. ... Her office is effective. And she translates that very savvily into an ability to connect out in rural Wisconsin in a way that isn't all that remarkable, it's just notable because of how little the Democrats are able to do that, usually," said a Wisconsin GOP strategist who is familiar with some of the possible candidates' thinking, who asked to be quoted anonymously to speak more candidly.

Baldwin's appeal across the state was underscored in 2018 when she won by almost 11%, even winning counties that voted for former President Donald Trump.

Baldwin's formidable operation and the importance of every tight Senate race in 2024 has Republicans in Wisconsin expecting virtually every stopped to be pulled out -- including having party elders intervene if needed.

"As soon as the first dirty pitches thrown, I think [former Govs. Tommy] Thompson or [Scott] Walker would step in and say, 'Enough's enough. We've seen this before. This isn't how we're gonna win a general election,'" McCoshen said.