Republican candidates walk back pledge of support for party nominee

15 facts you didn't know about John Kasich

1. He has twin daughters

In the photo above. Kasich and his wife, Karen, stands with his two 16-year-old daughters Reese and Emma after launching his presidential campaign. less 15 facts you didn't know about John Kasich

1. He has twin daughters

In the photo above. Kasich and his wife, Karen, stands with his two 16-year-old daughters Reese and Emma after launching his presidential ... more Photo: John Minchillo, STF Photo: John Minchillo, STF Image 1 of / 47 Caption Close Republican candidates walk back pledge of support for party nominee 1 / 47 Back to Gallery

None of the three remaining Republican presidential candidates could affirm Tuesday that they would support their party's nominee, paving the path toward an ugly fight at the GOP convention in July.

During a town hall interview with CNN, Donald Trump, the Republican frontrunner, explicitly walked back a pledge he and his rivals signed in September, agreeing to rally behind their party's nominee.

RELATED: Trump signs pledge to back GOP's 2016 presidential nominee

When asked if still honored the pledge, Trump said, "No, I don't anymore."

The Republican National Committee said in a statement Wednesday, "The pledge is simple, each candidate agreed to run as a Republican and support the nominee."

The pledge, however, does not hold much sway, said Charles Sartain, assistant general counsel for the Republican Party of Texas and a lawyer at Gray Reed & McGraw in Dallas.

"There's no real way to enforce the loyalty pledge, and there is no way to force a candidate to support the party nominee," he said, citing the rules of the RNC.

Trump's reversal comes amid widespread chatter of electing an alternate nominee at the party's convention, even if Trump goes in with a lead in delegates and primary votes.

Mark Jones, a political scientist at Rice's Baker Institute, rattled off the sequence of past primaries since the 1970s, both Republican and Democrat, but couldn't recall a race in which candidates widely declined to pledge their support to a party nominee.

"The level of rancor is so high, and this just fuels it," he said. "This takes an already very volatile and very tense convention setting and makes it even more so."

If no candidate claims an outright majority before the convention, party rules require a series of re-votes that would allow delegates to switch their allegiance and select a candidate other than the frontrunner.

RELATED: Growing chance of contested convention puts added focus on delegates

Trump has suggested his supporters would riot if he were to enter the convention as the frontrunner and leave without the nomination.

He told CNN Tuesday that he had "been treated very unfairly" by "the Republican Party [and] the establishment."

"That Trump is signaling that now probably means that we'll start to hear more about the threat of an independent candidacy," Jones said.

A third party Trump campaign would certainly spell disaster for the GOP in the general election. The likelihood of that scenario increased as the other candidates declined to pledge their support to the frontrunner if he were to win the nomination.

"I'm not in the habit of supporting someone who attacks my wife, who attacks my family," Cruz told CNN, in reference to a recent Twitter feud focused on the candidates' wives.

RELATED: Lindsey Graham on presidential Twitter fight: 'knock this crap off'

Cruz wouldn't say whether he'd support Trump as the nominee, insisting instead that Trump would not be the nominee.

Ohio Gov. John Kasich also loosened the terms of the September pledge, telling CNN he would not back a nominee that he sees "as hurting the country."

"This just underscores the animosity that exists within the Republican Party," Jones said.