The final debate before next week’s Indiana Republican Senate primary quickly became a test of one thing: Who has the best Trump credentials?

Rep. Luke Messer used his opening statement to say he’d be a “true ally” of President Trump to help “make America great again.” Rep. Todd Rokita followed by saying he was the most trusted candidate to “support our president in draining the swamp.” And later, Mike Braun said Trump was the “inspiration” for his run for office and highlighted his business background: “Just like President Trump, I’ve built real things.”

The theme was indicative of that coloring many Republican primaries across the country: Seeking support from Trump’s loyal base of voters, candidates are going to extraordinary lengths to link their credentials to the president. In a trio of races with May 8 primary elections -- Indiana, Ohio and West Virginia -- Trump has become perhaps the central message in the final stretch.

One Republican strategist, who requested anonymity to assess candidates’ strategies, said there is “no such thing as ‘Team Not Trump’” among Republican primary voters.

“The animosity and hatred level of the left attacking the president’s legitimacy has translated into everybody on the conservative side putting their jersey on,” the strategist said, pointing to Trump’s high support among GOP voters in polls. “If you’re running in a primary, you have to communicate and make sure voters understand that you have your jersey on too and that you are glad to have the president’s enemies as your enemies.”

Rokita and Messer doubled down on Wednesday. Rokita released an ad linking incumbent Democrat Joe Donnelly to Robert Mueller, the Department of Justice special counsel, and asking: “Who’s tough enough to stop the witch hunt?” Not to be outdone, Messer released a letter officially nominating Trump for the Nobel Peace Prize for his promising efforts to negotiate with North Korea. Of the 17 Republican House members who signed the letter, four are running for Senate, and one is locked in a gubernatorial primary.

In Ohio, Rep. Jim Renacci is viewed as the frontrunner of a much quieter, less acrimonious primary than the other two. But he still faces several challengers, most notably businessman Mike Gibbons, who has invested his own money in the race. In what may be the only public poll of the race, conducted in early April, Renacci was the only candidate with double-digit support, but nearly two-thirds of the primary electorate remained undecided.

Trump endorsed Renacci last week, and the Trump re-election campaign followed up with an endorsement Tuesday of the Ohio Republican, who hopes to take on incumbent Sherrod Brown.

“As I travel this state, I see more and more people, that’s the first thing they ask me, ‘Do you support this president?’” Renacci told Fox Business Channel on Wednesday. “I say I absolutely do and they’re happy to hear that.”

“Everybody in the primary talks about being with the president. I’m the only one who has the support of the president,” the congressman added.

Gibbons spokesman Chris Schrimpf offered a different view:

“If you look at which candidate most Trump voters are going to find appealing, most of them will like Mike Gibbons more than a career politician in Washington, D.C.,” Schrimpf said, pointing out that the candidate served as a co-chair of Trump’s Ohio campaign. “I think Ohio voters know Mike Gibbons is a strong Trump supporter.”

Though the effort to court Trump supporters is the same, candidates’ messaging strategies differ greatly. Messer, a member of House GOP leadership and a low-key campaigner, has pitched himself as the staunchest backer of Trump’s agenda and attacked Rokita for voting against a spending bill earlier this year, saying his colleague had not been there for the hard votes. Rokita, who is more brash, has pitched himself as the hard-charging defender of the president. In the debate, he called the special counsel investigation into Trump’s campaign a “witch hunt.”

“It comes down to: Who do you trust to be strong enough with the president to defend him?” Rokita said.

Braun, meanwhile, has attempted to own the outsider label in the race, highlighting similarities between his background and Trump’s and calling his two opponents “swamp brothers.”

Andy Surabian, a Republican strategist and former special assistant to the president in the White House, said it is important for candidates tethering themselves to the president to do so in a way that fits their style rather than mimic Trump and seem inauthentic.

“Every candidate is wrapping their arms around America First Trumpism: ‘I’m the most ‘MAGA’ candidate there is,’” Surabian said, using an acronym for Trump’s slogan, Make America Great Again. “It’s not like everyone is trying to mimic Trump’s speaking style, but they certainly all are trying to wrap their arms around him and his agenda.”

In West Virginia, where Republicans hope to unseat Joe Manchin, it’s much the same. In the final candidate debate Tuesday night, which aired live on Fox News, Attorney General Patrick Morrisey pointed out that he was part of the Electoral College vote for Trump, citing that as evidence that he can be trusted as an ardent supporter. Rep. Evan Jenkins argued that he is the staunchest defender of the president’s agenda, having supported his tax cuts and deregulation efforts on Capitol Hill. The two candidates have spent much of the primary hurling bombs at each other, and the debate was no different.

Jenkins, who has previously run ads calling Morrisey a “Never Trumper,” asked him pointedly who he voted for in the 2016 presidential primary. Morrisey responded, “I support the president” before firing back: “Evan supported him the day before the primary. That’s no profile in courage.”

Meanwhile, Don Blankenship, a former coal baron who spent a year in prison for conspiring to violate mine safety standards, has pitched himself as an outsider in the race, and has owned a particular brand of Trumpism with his brash, controversial remarks , most of them aimed squarely at Majority Leader Mitch McConnell.

But Blankenship has also been slightly more willing than either Jenkins or Morrisey to allow daylight between himself and Trump, if only slightly. In a debate last month, the candidates were asked if there was anything they disagreed with Trump on. Morrisey and Jenkins both used it as an opportunity to heap praise on the president: Morrisey called it a “historic presidency” and Jenkins said Trump was doing a “darn good job.” Blankenship, however, cited several disagreements. He said he didn’t support the president’s “personal behavior sometimes” and that he had concerns about foreign policy, that there is a tendency to police the world at the expense of the American taxpayers. Still, he didn’t linger on the disagreements.

“I agree with [James] Comey that his tie’s a little too long and I think he tweets too much,” Blankenship said, citing a sartorial critique written by the former FBI director in his new book. “But if that’s the only failings that he has, I think we’re in for a great six years ahead of us, or seven, and I think we should all be very grateful we have President Trump.”

Outside money has streamed into West Virginia aiming to shape the primary race in the final weeks. Duty and Country PAC, a Democratic outside group, is running ads attacking Jenkins and, to a lesser extent, Morrisey. The group is ignoring Blankenship, who is being attacked by outside groups linked to national Republicans. Mike Plante, a Democratic strategist in the state and adviser to the outside group, said Trump remains popular and called it a wise strategy for Republicans to link themselves to the president. But he maintained that Trump wouldn’t be enough to carry either candidate over the top.

“They’re still going to have to defend their own records and run on their records,” Plante said. The question remains: Will the president’s coattails alone be enough? The more voters learn about Morrisey and Jenkins, the less, I think … effective the president’s coattails will be.”