The presidential primary has been a wrenching experience for the GOP so far — and it’s about to get even worse.

Donald Trump Donald John TrumpObama calls on Senate not to fill Ginsburg's vacancy until after election Planned Parenthood: 'The fate of our rights' depends on Ginsburg replacement Progressive group to spend M in ad campaign on Supreme Court vacancy MORE, Ted Cruz Rafael (Ted) Edward CruzSenate Republicans face tough decision on replacing Ginsburg Cruz: Trump should nominate a Supreme Court justice next week Renewed focus on Trump's Supreme Court list after Ginsburg's death MORE and John Kasich have all backed away from their pledge to support the party's eventual nominee, foreshadowing a fight at the convention and beyond that could cleave the GOP into warring factions.

ADVERTISEMENT

"This race is kind of at its boiling point," said Matt Mackowiak, a GOP strategist and contributor to The Hill. "As ugly as it is now, the two losing candidates at the convention are going to feel even worse."

Instead of helping to unify the GOP behind a candidate, as the primary process typically does, the race has instead created deep wounds between the candidates that are unlikely to heal.

The antagonism has been heightened by a particularly vicious stretch of campaigning involving allegations of adultery and pictures of the candidates’ wives.

"I believe that we're beyond the point in the campaign where we feel we can unify. There’s been too much bad blood that's been created," said GOP strategist David Payne, who said he would like to see Cruz win the nomination before the convention.

Cruz, the closest rival to Trump in the delegate count, acknowledged Wednesday that Trump's attacks on his wife, Heidi, have made him reconsider his pledge to the Republican National Committee to support the GOP nominee.

“I’m not in the habit of supporting someone who attacks my wife and attacks my family,” Cruz said during a CNN town hall Tuesday night. "That is going beyond the line."

Kasich, who also made the pledge, appeared to back away from his promise as well.

"Frankly, all of us shouldn't even have answered that question," Kasich said late Tuesday, referring to when candidates where asked to make the pledge at the first GOP debate in August.

Trump was the most definitive on revoking the pledge.

"No, I don't anymore," he told CNN's Anderson Cooper on Tuesday when asked if he continued to support the eventual nominee.

"I have been treated very unfairly," Trump continued. Asked by whom, Trump responded, "basically by the [Republican National Committee], the Republican Party, the establishment."

The businessman on Wednesday morning reiterated that his support for the Republican nominee is conditional.

"I just want to see who the GOP nominee is," Trump said on ABC's "Good Morning America.”

The RNC engineered the loyalty pledge last summer after Trump floated the possibility of running as a third-party candidate in an interview with The Hill.

After facing pressure, the businessman made a show of signing the pledge, holding an impromptu press conference at Trump Tower where he held up the paper for the world to see.

But the businessman insists his pledge was conditional on being treated fairly by the Republican Party — something he says hasn’t happened, now that there is a movement to deny him the nomination.

Trump's opponents have launched a large-scale effort to prevent him from reaching the 1,237 delegates he needs to win, which would force a contested convention for the nomination in July.

"The pledge was always pretty hollow to begin with," said Rory Cooper, a former House GOP leadership aide who is now advising the new #NeverTrump super-PAC. "I'm happy that it's behind us."

"Nobody expects Donald Trump to be a man of his word in any sense. That would certainly apply to the pledge as well," Cooper said.

The #NeverTrump super-PAC aims to deny Trump delegates with strategic ad buys. The group is now running ads in Wisconsin supporting Cruz, plans to support Cruz in California and may support Kasich in Pennsylvania.

Trump has 736 delegates so far, according to The Associated Press’s delegate tracker. Based on current projections, GOP strategist Ford O'Connell said Trump is likely to either barely reach 1,237 or fall just short.

If Trump manages to win the nomination outright, it’s likely that a group of Republicans will break away, potentially putting forward a third-party candidate.

But if a contested convention results in Trump losing the nomination despite leading in delegates, it’s an open question whether he — and his supporters —would rally behind the nominee in the general election

"It's going to be a fight. It's going to be embarrassing for us," Payne added about the possibility of a convention fight that could "play out in prime time."

Many Republicans strategists say they don't think Trump will attempt a third-party bid if he fails to win the nomination, given that it’s too late to get on the ballot in most states.

But should Trump opt for a write-in campaign, it could effectively dash any Republican hopes of beating the Democratic candidate.

"Republicans — the core Republicans — are going to rally around” the nominee no matter who it is, O'Connell insisted.

Still, "the enthusiasm is with Trump. How other candidates might pick that up if they're the nominee is an open question," O'Connell added.

Democrats are watching the spectacle unfold with glee.

"Friendly reminder that the GOP candidates don't even want to vote for the GOP candidates," former Rep. John Dingell (D-Mich.) tweeted late Tuesday.