(Image Credit: Charles Krupa/AP Photo)

Although the Senate just jumped a procedural hurdle, clearing the way for a fresh debate on gun control, two hard-right conservatives in the House of Representatives have worked in the past week to collect signatures on a letter to House Speaker John Boehner discouraging him from bringing any new gun measures to the floor without support from a majority of the House Republican Conference.

The effort is being led by Reps. Paul Broun, a Senate hopeful gunning for Georgia's open seat, and Steve Stockman, a Texas Republican who gained notoriety earlier this year for inviting rocker/2nd Amendment-defender Ted Nugent to the State of the Union.

"We are writing to express our strong opposition to legislation requiring private sale background checks for firearms purchases," the letter reads. "Under the precedents and traditions of the House, we would ask that no gun legislation be brought to the floor of the House unless it has the support of a majority of our caucus."

That majority within the majority is also known around the Capitol as the Hastert Rule, after former GOP Speaker Dennis Hastert of Illinois. Boehner has broken it on key votes this year, testing his speakership, such as votes on the Fiscal Cliff agreement, Violence Against Women Reauthorization Act, and emergency relief for victims of Superstorm Sandy.

Boehner has long-maintained that he aspires to be the Speaker of the Whole House of Representatives, not just House Republicans, although it's a tricky high-wire act to execute and one more slip could cost Boehner his perch atop the party.

The speaker today emphasized that he does not feel beholden to the informal rule.

"It was never a rule to begin with," he said. "Certainly my prerogative or my intention is to always pass bills with strong Republican support."

Although Boehner has recently come under fire for violating the unspoken rule five times over the past three years, Nancy Pelosi broke it on seven pieces of legislation during her tenure as Speaker, while Hastert did so 12 times and Newt Gingrich needed minority majorities on six measures.

Boehner reiterated Wednesday that he will wait for the Senate to pass a gun measure before the House reviews it or potentially acts on it. In the meantime, he says, House committees will continue reviewing the issue as well.

A spokesman for Rep. Stockman says more than 45 Republicans have signed the letter, although it's doubtful a "Hastert majority" of the House GOP will endorse it.

"The so-called 'universal background check' would be a violation of a constitutionally-guaranteed right on an unprecedented scale," Broun and Stockman write in a letter seeking signatures. "The [National Rifle Association], [Gun Owners of America] and other gun groups have made available a substantial amount of research on the dangers of universal background checks, which we would be happy to pass along."

A full copy of the letter is posted here.