One of the nation's largest Tea Party groups is warning congressional Republicans to watch their right flank ahead of a final vote this week on the long-term budget deal that averted a government shutdown.

Mark Meckler, co-founder of Tea Party Patriots, says dissatisfaction with the budget deal has local activists already seeking out primary challengers to sitting House GOP members who are supporting the deal.

"I'm literally getting emails by the hour from people talking about primary challenges," Meckler told The Ballot Box, adding that opposition to the deal among grassroots conservatives has been building all week.

Despite some vocal opposition from House and Senate conservatives, however, Republicans on Capitol Hill are largely rallying around the deal to cut $39.9 billion from current spending levels. House Majority Leader Eric CantorEric CantorEric Cantor offering advice to end ‘immigration wars’ Trump's olive branch differs from the golden eras of bipartisanship After divisive rally, Trump calls for unity MORE (R-Va.) predicted Tuesday that the House will pass the bill with "strong Republican support."

Should that happen, said Meckler, he expects threats of primary challenges to GOP members to increase.

"I'm hearing it from just about every district where someone voted yes [on the deal]," he said of the potential targets. "It's a pretty easy list, actually. All you have to do is look at the roll call."

Meckler said the vast majority of activists he's been in touch with since Friday, when the deal was struck, "are not calming down." He said they are rejecting the argument coming from House Republicans that it's time to move on to the next fight and focus on Rep. Paul RyanPaul RyanRyan: Graham-Cassidy 'best, last chance' to repeal ObamaCare Ryan: Americans want to see Trump talking with Dem leaders Overnight Finance: CBO to release limited analysis of ObamaCare repeal bill | DOJ investigates Equifax stock sales | House weighs tougher rules for banks dealing with North Korea MORE's (R-Wis.) proposed budget.

Tea Party Patriots doesn't officially endorse candidates, but its local coordinators play a role in recruiting and identifying them.

If a "yes" vote on the budget compromise has activists across the country irked, Meckler suggested a "yes" vote on raising the debt ceiling could be enough to officially bring out the primary challenges. Many House Republicans are already talking tough on the impending debt-ceiling vote, but some at the grassroots level have expressed disappointment that House leaders have all but conceded that the limit must be raised.

"I think it all will become clearer after the debt-ceiling debate," Meckler said. "Either the folks in there now will do the right thing, or we'll give up and start looking for the next round of people to elect."