Wisconsin Republicans are waiting anxiously for Sen. Ron Johnson (R-Wis.) to make a decision on whether he will run for reelection and are quietly considering backup plans in case he doesn't run.

Johnson made national headlines last week when he told conservative commentator Lisa Boothe that he did not think he was the best candidate for 2022, leading many to ask whether this was foreshadowing a retirement.

“I believe that he, in his heart I’m not so sure he wants to run, but at the end of the day he doesn’t want to turn everything over to [Senate Majority Leader] Chuck Schumer (D-N.Y.),” Wisconsin state Assembly Leader Robin Vos (R ) told The Hill. “He’s probably the strongest candidate that we have."

Other Wisconsin Republicans point to Johnson’s popularity among the conservative base in the state and recent fundraising efforts as signs he is leaning toward running.

“I would recommend to everybody to not underestimate Ron Johnson,” Wisconsin-based GOP strategist Brandon Scholz told The Hill. “He is very much in tune with what he wants to do and when he wants to do it.”

Johnson raised $1.2 million in the second quarter of this year, outraising the growing group of Democratic Senate hopefuls in Wisconsin. Johnson had a cash-on-hand total of $1.7 million going into July after the latest Federal Election Commission filing.

Others remain skeptical that Johnson is leaning toward running, pointing to a lean staff. The Republican only has a finance director on the political side right now. Six years ago at this point, Johnson had a full staff, including a campaign manager and a communications team.

“If he’s genuinely thinking about pulling the trigger on the campaign, I’d expect him to start staffing up sooner than later,” said one Wisconsin-based Republican strategist.

Democrats are salivating over the chance to run against Johnson, who has given Democrats plenty of fodder for political attacks.

Wisconsin Rep. Gwen Moore (D) endorsed progressive candidate and Lt. Gov. Mandela Barnes (D) for the Senate race on Tuesday, calling Barnes “the best candidate to beat Ron Johnson.”

Johnson has come under scrutiny for a number of comments this year including saying the Jan. 6 attack on the Capitol was “peaceful,” for dismissing climate change as bullshit at a GOP luncheon, and for organizing an event highlighting adverse reactions to the COVID-19 vaccine.

The senator more recently came under scrutiny for questioning the effectiveness of masks in stopping the spread of coronavirus amid new guidance from the Centers for Disease Control and Prevention.

Wisconsin Republicans have publicly brushed off the controversies.

“When somebody in office is getting beat up a lot, it’s probably because they’re doing something worthwhile because they’re getting a reaction from the other side,” said Stephanie Soucek, the chairwoman of the Door County Republican Party

But behind the scenes, Republicans worry that Johnson’s controversies could hurt him in the swing state.

“We all know how purple it has become at this point. That might help you in the primary,” said the GOP strategist. “You kind of have to almost tone down those culture war issues so that you’re positioned for that general election here.”

Other Republicans have brushed this off, arguing that any Senate race in Wisconsin will be a nail-biter for both sides.

“If somebody wants to say ‘oh well, Johnson’s in trouble, it’s going to be close,’ any statewide candidate in Wisconsin is going to be close and if close means trouble, then they’re all in trouble,” Scholz said.

Biden narrowly defeated Trump last year in Wisconsin by less than a percentage point. In 2016, Trump had become the first Republican presidential candidate to flip the state in decades. He also won by less than a percentage point.

In the 2018 midterm elections, Gov. Tony Evers (D) narrowly defeated then-Gov. Scott Walker (R ), also by less than a percentage point.

“We’re really at a point where our statewide races are going to be one-, two-point races,” Scholz added.

Democrats increasingly see the state as a prime pick-up opportunity, and eight Democrats including Barnes have jumped into the race. Johnson would be the only incumbent Republican running in a state won by President Biden in 2020, and the nonpartisan Cook Political Report rates the race as a “toss-up.”

Other Republican names have been floated as possible replacements, including Rep. Mike Gallagher (R-Wis.), Marine veteran and former Senate candidate Kevin Nicholson, former Rep. Sean Duffy (R-Wis.) and former Senate candidate Eric Hovde.

Gallagher raised nearly $625,000 in the second quarter, fueling speculation that he was exploring a potential bid if Johnson does not run. Johnson is said to believe that Gallagher is the best candidate to replace him in such a scenario. But some Wisconsin Republicans have questioned Gallagher’s statewide appeal.

"He has limited appeal outside of his district and he doesn’t have a statewide network,” said a second Wisconsin GOP strategist.

Gallagher has become known for his interest in foreign policy, with a particular focus on China. He notably criticized Trump after the Jan. 6 attack on the Capitol, writing in an op-ed that the former president “bears responsibility” for the attack and called the efforts to overturn Biden’s Electoral College victory “unconstitutional and dangerous.”

The congressman did not vote to impeach Trump, but his comments have led some Republicans to question what role the former president would play in Gallagher’s future campaigns.

"In this new primary world with Trump trying to weigh in and pick his people, the most difficult thing for a Gallagher is going to be what is Trump going to do?” said the same strategist. “The stuff that Gallagher came out with is going to put him in a hard spot."

Johnson has become the de facto leader of the Wisconsin Republican delegation given the departures of Walker, former Speaker Paul Ryan and Reince Priebus, the former Republican National Committee chairman and chief of staff to Trump.

As a result, his departure would raise questions about the future of the GOP in Wisconsin.

For now, the party is anxiously awaiting Johnson’s decision.

“The only person who knows what Ron is going to do is Ron himself. If he does,” the first GOP strategist said.