(The Hill) — GOP lawmakers in the House are tearing apart a Senate gun control package crafted by a bipartisan group of senators, lashing out at fellow Republicans who support the legislation in the process.

Rep. Lauren Boebert (R-Colo.), co-chair of the Second Amendment Caucus, called the 14 Senate Republicans who voted to advance the legislation on Tuesday RINOs – Republicans In Name Only.

“We all know that Bernie Sanders is going to vote to take away your guns. He ran on that platform. But I do think that it’s surprising some of the other 14 Senators who ran on preserving Second Amendment rights, have decided to turn their back on their commitment,” Boebert said in a press conference Wednesday. 

“I’m sure we’ll even see some in the House, unfortunately, who have touted their support of the Second Amendment and Americans to have the right to keep and bear arms and they will fold,” Boebert said.

“We did not anticipate that we will be playing defense against the Republican senators on preserving the Second Amendment,” said Rep. Thomas Massie (R-Ky.), the other co-chair of the Second Amendment Caucus.

Former President Trump also weighed in, calling Sen. John Cornyn (R-Texas), the lead Republican negotiator, a “RINO.” Trump also criticized Senate Minority Leader Mitch McConnell (R-Ky.), who is backing the measure.

The bill was crafted in the wake of a pair of shootings that shook the nation.

Days after a racist shooting at a Buffalo supermarket left 10 people dead, a shooter in Uvalde, Texas killed 19 elementary schools and two educators.

The shocking crime led to the Senate deal and has Congress on the verge of passing the first major congressional action on gun control legislation in decades.

Dubbed the Safer Communities Act, the bill includes enhanced background checks on juvenile records for those between the ages of 18 and 21; provides grants for state-level red flag laws; closes the “boyfriend loophole” to those convicted of a domestic violence offense from buying guns; new penalties for straw purchasing of firearms and illegal firearm trafficking, and expands funding for community mental health services.

To those calling for Congress to take action amid a plague of mass shootings, the bill doesn’t go far enough.

But it drew opposition from the top two House GOP leaders on Wednesday and is likely to be opposed by the vast majority of the conference.

The red flag funding provision is evoking the most pushback from gun rights advocates. 

“Red flag laws permit the preemptive seizure of firearms from Americans without due process by allowing any person to report a gun owner to law enforcement and petition for the confiscation of that individual’s firearms, even before the gun owner has an opportunity to defend themselves,” the House Freedom Caucus said while announcing its formal opposition to the bill on Tuesday.

McConnell, one of the 14 Senators who backed the legislation, defended the measure, calling it “a commonsense package of popular steps that will help make these horrifying incidents less likely while fully upholding the Second Amendment rights of law-abiding citizens.”

Massie, who represents a district in McConnell’s home state, said the Senate GOP leader was acting in his capacity as minority leader rather than as a senator representing the conservative state of Kentucky.

Rep. Dan Bishop (R-N.C.) said that McConnell is playing to the ideological middle in order to build a slim majority.

“I personally don’t think that’s what America wants or needs. I think America is looking for people who will come out and explain to the people, remind them what the foundation of the Second Amendment is, why it exists, why we’re free substantially because of it,” Bishop said. “I believe that produces victories in the election far more than chasing the last vote.”

House GOP leaders will formally whip members to vote against the bill. 

A House GOP whip check notice calls the legislation part of “an effort to slowly chip away at law-abiding citizens’ 2nd Amendment rights.”

The bill “transforms law-abiding citizens under the age of 21 into second-class citizens by creating a de facto waiting period of up to ten business days for legal, law-abiding firearm purchases,” the whip check notice said.

House Minority Leader Kevin McCarthy (R-Calif.) and House Minority Whip Steve Scalise (R-La.) told their members in a House GOP Conference meeting on Wednesday that they would vote against the legislation, positions that won praise from House conservatives in the Second Amendment Caucus.

Some House Republicans are expected to vote for the Senate bill when it comes to the House.

Rep. Tony Gonzales (R-Texas), whose district includes Uvalde, said Wednesday that he supports the Senate gun legislation.

New York GOP Reps. John Katko and Chris Jacobs, neither of whom are running for reelection, announced support for the bill on Tuesday. Jacobs abandoned his reelection campaign after he received heavy backlash from other Republicans when he came out in support of an assault weapons ban following the Uvalde shooting.

Several other House Republicans could also vote yes on the bill. In a series of votes on a more stringent gun bill passed by the House earlier this month, 10 House Republicans voted in favor of raising the age to buy assault-style rifles from 18 to 21.

The vocal critics in the Second Amendment Caucus did not go so far as to say that they would campaign against those who voted for the legislation. But several gun rights groups have named the bill the vote a “key vote,” and have aggressively campaigned against Republicans who did not vote their way in the past.