A pro-gun lobby group broke ranks with the powerful National Rifle Association (NRA) on Sunday, stating it would endorse a bill that includes expanded background checks.

The Citizens Committee for the Right to Bear Arms, which is said to represent around 650,000 members, told its supporters via email that it was backing proposed legislation due to go before the Senate this week.

The news was later confirmed by senator Joe Manchin – one of the architects of the comprise bill – in a tweet.

A spokesman for the pro-gun rights group later told the Washington Post that they had decided to back the legislation because "we believe it is the right thing to do".

But it comes just days after the group sent out a press release seemingly mocking the concept of wider background checks on buyers and suggesting that gun laws never work.

"If politicians want universal background checks, we should start with them," Alan Gottlieb, the Citizens Committee chairman wrote in a statement released on Wednesday.

He continued: "People who make the laws we have to live under break them anyway, just like criminals routinely disobey gun laws. Based on their own experience, politicians should know that the gun laws they pass will not prevent crime."

The bill proposed by Manchin, a Democrat, and Republican senator Pat Toomey would see background checks increased to cover both commercial sales both online and at gun shows. But private sales would be exempt.

The NRA had initially said the compromise was a "positive development" but later hardened its stance, and threatened political retribution to any senators who backed the bill.

But an email from the Citizens Committee to its members suggests that the Manchin-Toomey compromise satisfies its demands.

The website Politico.com quoted the message as contrasting Manchin and Toomey's "balanced approach" to more "draconian" measures being proposed by gun control advocates.

A vote on the comprise bill could come as early as Wednesday, lawmakers said Sunday.

"We expect the vote this week. Wednesday is probably the most likely day for the Manchin-Toomey alternative," said Toomey on CNN's State of the Nation.

But even with the support of anti-gun groups such as Michael Bloomberg's Mayors Against Illegal Guns and, now, one group on the other side of the debate, it is not clear if there exists enough political will in Washington to push the legislation through.

"It's an open question whether we have the votes. I think it's going to be close," Toomey said Sunday.

guardian.co.uk © Guardian News and Media 2013


Photo: Flickr user Gage Skidmore.