Former Massachusetts Gov. Bill Weld may be it when it comes to Republicans primary-challenging President Trump for the 2020 GOP nomination.

Popular two-term Maryland Gov. Larry Hogan – who had flirted with a White House run and this spring made stops in Iowa and New Hampshire – is now out of the running.

LARRY HOGAN SAYS NO TO 2020 PRIMARY CHALLENGE AGAINST TRUMP

“I truly appreciate all of the encouragement I received from people around the nation urging me to consider making a run for President in 2020. However, I will not be a candidate,” Hogan tweeted on Saturday.

One day earlier, another vocal Trump critic appeared to signal he was shying away from taking on the president in the primaries.

“I don't see a way to get there,” former two-term Ohio Gov. John Kasich, a senior CNN political commentator, said Friday in an appearance on the cable news network.

“Right now, there’s no path,” he acknowledged.

KASICH: 'RIGHT NOW, THERE'S NOT PATH'

Still, top Kasich political adviser and veteran GOP consultant John Weaver told Fox News minutes later that “nothing has changed … every day the tables could turn.”

And the former governor himself took to Twitter hours later to temper his original comments, saying “that while the path looks tough, all of my options are on the table.”

Kasich’s second place finish in the 2016 New Hampshire Republican primary behind Trump turned the one-time longshot for the nomination into a potential contender that year. But in the ensuing months, the only primary he was able to win was in his home state.

Kasich never endorsed Trump during the 2016 campaign, even after Trump locked up the nomination. And Kasich didn’t attend that summer’s Republican nominating convention, even though it took place in Cleveland, in his home state of Ohio. Since Trump’s entered the White House, Kasich’s remained a vocal critic of the president.

A Pew Research Center poll conducted April 29-May 13 indicated that 43 percent of Republicans and Republican-leaning independents wanted to see a primary challenge against the president.

But public opinion surveys also indicate that Trump remains extremely popular among Republican voters.

“Among most Republicans it’s seen as a fool’s errand,” said former New Hampshire Gov. John H. Sununu, who served as chief of staff to President George H.W. Bush.

“The president’s got very strong support among Republicans and it appears to be getting stronger and stronger every day,” explained Sununu, a Fox News contributor.

Ryan Williams, a veteran GOP consultant and spokesman for Mitt Romney’s 2012 presidential election, predicted that “President Trump is all but assured the Republican nomination and any potential Republican challenger should understand that.”

“If you’re an incumbent politician like Gov. Hogan or a former politician with a TV gig like Gov. Kasich, I think you have to take a look at the numbers and see that this would be a fruitless endeavor to challenge him,” explained Williams.

He added that unlike Hogan and Kasich, “for someone like Gov. Weld, who’s been out of politics for a few years, it’s a no lose situation for him. He can run, have fun. He won’t win but in the process, he won’t damage himself.”

Weld, who officially launched his primary challenge in April after exploring a bid for two months, says time’s on his side.

“The president is just abdicating his responsibility as president. I think that is so outrageous that I think it’s going to sink in over time in the consciousness of the American people that we can’t have this guy doing this job,” he charged in a recent interview with C-SPAN.

And Bill Kristol, a leader of the never-Trump movement, also isn’t giving up.

“I have a high regard for Larry Hogan, and Marylanders are lucky to have him as governor. Needless to say, the fight for our party and our country will continue,” he wrote on Twitter following Hogan’s announcement on Saturday.

And Kristol added “Aut inveniam viam aut faciam,” which is Latin for “I shall either find a way or make one.”