In Pennsylvania, the ice beneath Donald Trump is cracking

PITTSBURGH -- In 2016, then-Reps. Lou Barletta, R-Pa., and Tom Marino, R-Pa., became the first sitting members of Congress to endorse then-candidate Donald Trump for president. Their colleagues in Washington gave them the side-eye. Barletta told me at the time that when that didn't work, their colleagues tried to talk them out of it.

It didn't work. The two traveled throughout the state and sometimes in other states, earning the nickname "Thunder and Lightning" from Trump on the trail. It turned out they were onto something. They broke the streak that year of Republican presidential candidates losing Pennsylvania, which had been intact since 1992.

On Friday, in keeping with their willingness to put it all on the line, Thunder and Lightning were back -- only this time, not for Trump. Instead, Barletta and Marino called on Gov. Ron DeSantis, R-Fla., to run for the Republican nomination in 2024 in a tweet: "More than ever our country needs strong leadership, someone that gets things done & isn't afraid to stand up for what's right. So Tom Marino & I are calling on our former colleague @RonDeSantisFL to run for president in 2024. Come on Ron, your country needs you!"

David Urban, a Washington-based strategist who was Trump's Pennsylvania adviser in 2016, said their endorsement for DeSantis is "a big symbolic deal."

Urban, a Pennsylvania native from Aliquippa, had a front-row seat to the two men supporting Trump ahead of the primary contests in 2016. "I cannot overstate their importance in 2016," he said. "They were credible, likable, mainstream Republicans who were, along with Chris Collins of New York, the first supporters on Capitol Hill. We used to meet in the Capitol Hill Club on Thursdays, and there were those three and eventually two or three others who joined along. Marino and Barletta were early, early and big, and vocal for the former president. Every time he came to Pennsylvania, they were there. Every time he traveled, they were there. I mean, they were die-hard Trump folks. And I think they could speak for themselves, but I think that they became very, just, upset with the president's actions during the post-election."

Then, in last year's Pennsylvania U.S. Senate and gubernatorial races, Trump supported far-right state Sen. Doug Mastriano and celebrity doctor Mehmet Oz. This was the straw that broke the camel's back for them, explained former Pennsylvania state party chairman Rob Gleason, who ran the party in 2016 and was also an early supporter of Trump.

Barletta was running in that crowded gubernatorial primary along with nine other candidates that included Mastriano. Marino took Trump to task for supporting Mastriano over Barletta, saying he threw the former congressman "under the bus."

Mastriano's loss to Democratic Gov. Josh Shapiro included the loss of traditionally red counties to the Montgomery County Democrat. Mastriano said this week that he was considering a run for the U.S. Senate in Pennsylvania next year.

"Since (Trump's) choices in the primary races last year, a variety of people have expressed concern about Trump, and that movement is growing," said G. Terry Madonna, a political science professor at Millersville University. "Right now, Trump has around 30% of the Republican vote, and as I've been telling people if he ends up in a series of primaries with four or five opponents, and they divide the anti-Trump vote, that's likely to help him win the nomination. One strong opponent, however, can rally his opponents instead of dividing the vote up," he said.

Madonna said that is why the Marino and Barletta endorsement means something. DeSantis has not announced his intentions to run for the Republican nomination for president -- nor will he until after his legislative session is over later this spring. But he is on a book tour that has taken him all across the country, including two events Friday in Iowa, and none of that is a coincidence.

The Florida governor, whose parents are from Aliquippa, Pennsylvania, and Youngstown, Ohio, will speak on April 1 in Harrisburg at the annual Pennsylvania Leadership conference. He is among eight featured speakers at the event scheduled to start on March 30.

Urban added that the question that needs to be answered after today is, "How many more Tom Marinos and Lou Barlettas are out there? They loved (Trump), they went to war for the guy. And now, they're moved on from the guy. What happens next is telling."

Salena Zito is a CNN political analyst, and a staff reporter and columnist for the Washington Examiner.