The fight over the fiscal cliff may be over for now. But for the GOP, the massive rift it helped open up isn’t likely to heal for a long time.

Tuesday’s late-night House vote to avert the fiscal cliff passed despite the opposition of nearly two-thirds of House Republicans. That’s left a bitter taste in the mouths of many of the party’s staunch conservatives.

The bill, which allowed the Bush tax cuts to expire for families making more than $450,000 and doesn’t significantly cut spending, “will lead to a profound fight in the GOP,” former House speaker Newt Gingrich told Politico Wednesday.

That fight may already be erupting. Among the House ‘no’ votes were the numbers 2 and 3 in the caucus: Majority Leader Eric Cantor and Majority Whip Kevin McCarthy. Their votes have already triggered talk that Cantor, who openly opposed the deal in a caucus meeting Monday, could mount a coup against Speaker John Boehner, with the backing of the most conservative lawmakers.

“I think there’s a tremendous dissatisfaction within the caucus over what’s occurred in the last two years—so many missed opportunities,” Rep. Tim Huelskamp, a staunch conservative who was recently purged from his committee assignment by the party leadership, told The Huffington Post.

Redstate.org’s Erick Erickson, a key conservative activist, is openly calling for the ouster of Boehner and Senate GOP leader Mitch McConnell, who helped negotiate the pact.

“Republicans who saw Mitch McConnell and John Boehner destroy the last plank of the Republican Party are going to need to look elsewhere for a savior for their party,” Erickson wrote Tuesday.

But in a sign of the acrimony swirling through Republican circles, Erickson likewise criticized Cantor and McCarthy for voting no. “This was opportunism, not courage,” he wrote.

The party’s potential presidential hopefuls were split, too. Senators Marco Rubio and Rand Paul, both Tea Party favorites, were among just five Republican senators to oppose the deal, while Budget chair Paul Ryan, hardly known as a moderate on fiscal policy, supported it, after reportedly changing his mind at the last minute.

Conservatives are angry about what they see as a Republican cave—not just because the deal ended the Bush tax cuts for the richest, but also because it failed to include significant spending cuts.

“This is a complete surrender on everything,” Washington Post columnist Charles Krauthammer said Tuesday on Fox News.

Tea Party Patriots, a leading grassroots Tea Party group, said on its website that the deal “raises taxes, avoids meaningful spending reductions, and proves Congress just isn’t serious about stopping overspending.”

Of course, the coming fights over sequestration and the debt ceiling—issues on which Tuesday’s bill kicked the can down the road—may offer Republicans a chance to regain their unity, since they’ll enjoy more leverage.

But the rift over the fiscal cliff could just as easily wind up setting a trend for the future. For over a decade, under what’s known as the “Hastert Rule,” after former speaker Dennis Hastert, Republican leaders have largely avoided bringing legislation to the floor that isn’t broadly supported by GOP members. This time, Boehner abandoned that principle to pass a bill with over twice as many Democratic votes as Republican ones. If Boehner concludes he can safely throw the Hastert Rule out the window, this could be just the first of many battles with more conservative lawmakers.