Brad Gold, Leigh Ann Caldwell, Alex Jaffe, and Jonathan Berger contributed reporting to this article.

Pennsylvania voters didn’t just back Donald Trump on Tuesday, they also picked 54 Republicans for the powerful posts of “unbound” delegates — party activists who can support anyone for president regardless of how their state votes.

That makes them crucial decision-makers for any open convention this summer, but most of the newly elected delegates have already made up their mind, according to an MSNBC tally.

At least 35 of the 54 delegates told MSNBC they will back Trump — although they can change their decision anytime, unlike most delegates.

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The majority of the newly elected delegates were wooed by senior campaign officials or the candidates themselves, reflecting the campaigns’ preparations for a potentially open convention. Twenty-seven told MSNBC they were skeptical of a joint Cruz-Kasich ticket. And in a shift from past primaries, several said the Trump campaign had a more successful operation than Cruz, perhaps because Pennsylvania was such fertile terrain for Trump’s message.

view photo essay The presidential campaign: Ted Cruz The Texas senator was first to announce his bid back in March, and has since been carefully laying the groundwork for a come-from-behind primary victory.

Carol Sides, a delegate backing Trump, said she was personally called by Heidi Cruz and Ivanka Trump, and this week she met with Donald Trump himself.

While the Cruz campaign dominated similar contests for unbound delegates in states like Colorado and North Dakota, it clearly struggled to find support in Pennsylvania.

In fact, the Texas senator even recommended supporters vote for delegates who, according to MSNBC’s reporting, are actually backing Trump.

A delegate recommended by Cruz, Joan Miller, said that while she got to meet privately with Cruz and Ohio Gov. John Kasich, she was uncommitted before Tuesday’s election.

“I was never was committed,” she told MSNBC, adding that Cruz aides “even asked and said they would help me get elected — isn’t that strange? None of us ever committed to him.” She is voting for Trump.

“I have no idea why the Cruz campaign put me on their slate,” said Aaron Cohen, a political consultant who noted that he never heard from the Cruz campaign.

Cohen won a delegate slot and said he is technically uncommitted, but will take Trump’s victory “into account” in his vote.

Close video Is the Cruz-Kasich deal unraveling? Ted Cruz’s campaign surrogate Rep. Mark Meadows and Former Special Assistant to President George W. Bush, Ron Christie, discuss the recent alliance between John Kasich and Ted Cruz and comment on whether this will actually help or hurt Donald Trump. Ted Cruz’s campaign surrogate Rep. Mark Meadows and Former Special Assistant to President George W. Bush, Ron Christie, discuss the recent alliance between John Kasich and Ted Cruz and comment on whether this will actually help or hurt Donald Trump. share tweet email Embed Staffing up

The Trump campaign has also been staffing up its delegate and convention operations, an effort that may have helped them win in Pennsylvania.

“Trump’s campaign was the first to contact me,” said Christopher Vogler, a delegate who ran unopposed. “Trump and Cruz’s campaigns have been more consistent.”

Vogler has been showered with attention from all the campaigns, including a call this week from Donald Trump Jr. and meetings with all three candidates. He said Trump was especially warm, complimenting Vogler on a delegate interview he did on Fox News.

While Vogler told MSNBC he is technically uncommitted, he emphasizes, “I take the results of the district very seriously,” and “Trump won the district handily.” Another delegate backing Trump, C. Arnold McClure, said he received a personal call from one of Trump’s others sons, Eric.

Coordination or collusion?

Several delegates said they disliked the coordination announced this week between Cruz and Kasich, and 27 opposed the idea of backing a Cruz-Kasich ticket at the convention.

Rick Morelli, a delegate backing Trump, said he liked Kasich as a potential running mate and he was “disappointed that they teamed up.”

Mike Puppio, another delegate backing Trump, said a “whole lot” of Republican voters in his district didn’t like Cruz and Kasich coordinating.

Mario Scavello, a delegate backing Trump, said she “lost respect” for Cruz and Kasich based on their alliance.

Vogler, the uncommitted delegate who leans towards supporting Trump because he won his district, said he didn’t care about Cruz and Kasich coordinating, but heard from many Republicans who did.

“Voters felt it was unfair,” Vogler said. “From my interaction, I think it hurt them more than it helped them in Pennsylvania.”

With all the public attention on Pennsylvania’s delegates, Vogler said he also received several threatening phone calls on election night.

“I received threats on my home phone,” he said. “People saying I better do the right thing if I know what’s good for me — it upset my daughter, who is 17.”

Vogler said the calls were “mostly Trump supporters,” and while he doesn’t think they represent Trump, he added, “on a personal level, as a husband and a father, it’s very upsetting — we can disagree, but there’s no place for that. This is America.”

Despite the setbacks, some delegates say the Cruz campaign continues to lay the groundwork for a potential open convention.

Privately, Cruz’s team isn’t conceding Pennsylvania’s delegates — despite Trump’s resounding win.

Tom Ellis, a newly elected delegate, said he received a call today from the Cruz campaign to gauge his support should there be multiple ballots at an open convention.

Ellis says he was “a bit surprised” they were already calling and “clearly planning for a contested convention.”

Ellis, a former Jeb Bush supporter, plans to back Trump on the first ballot but is uncommitted for potential later balloting. He said he’d take into consideration three priorities if he had to decide on a nominee at an open convention: “How close the candidate was on the first ballot, their vice-presidential possibilities and does Pennsylvania have a say in that, and who can beat Hillary Clinton.”