Leaders of the National Rifle Association plan to press members of Congress in the coming weeks to block the National Security Agency’s controversial program to collect records of Americans’ phone calls, arguing that the surveillance efforts can be used as a “backdoor” to construct a national gun registry.

“We will be up there and we will be making our feelings known,” David Keene, a member of the NRA’s executive board who served until this spring as the group’s president, told NBC News. “Our members are concerned about this. This metadata can be used to construct a list” of every gun owner.

Keene’s comments signaled a new determination by the gun lobby to take up opposition to the NSA surveillance efforts as a political cause, joining with civil liberties groups and others on the left who have been lobbying against the program for months, and potentially complicating the Obama administration’s efforts to preserve the phone surveillance program.

The comments came as NRA board members gathered this weekend in Arlington, Va., for a quarterly meeting and to celebrate the gun lobby’s latest political coup: Its defeat of two state senators in Colorado — including the state Senate president — in a special recall election pushed by the NRA as payback for the lawmakers’ support of gun control measures.

“Everybody is feeling insufferably proud of how things are going today,” said Grover Norquist, the veteran conservative activist who also serves on the NRA board.

Board members also will hear a report on the NRA’s surprise decision this month to file a friend-of-the- court brief on behalf of an ACLU lawsuit to halt the NSA collection program as an unconstitutional violation of American privacy rights. Norquist predicted the move, which is being promoted on the web page of the Institute for Legislative Action, the NRA’s lobbying arm, will tip the political balance in Congress over the issue.

“This is the beginning of a game changer,” Norquist said. “It will solidify conservative and Republican opposition to the program, without endangering the left-of-center opposition. … If you’re the (Obama) administration, you will begin to offer tactical retreats. ”

Laura Murphy, legislative director for the ACLU in Washington, recruited the NRA to join efforts to stop the program and said its participation will have a big impact. “We’ve got momentum going,” she said. “They (the NRA) have got access to all the Republicans.”

Murphy said a recently declassified FBI training manual on how agents can use their authorities under the Foreign Intelligence Surveillance Act in the course of terrorism and espionage cases helped sway the NRA leadership. The manual, a copy of which she provided to NBC News, instructs agents how they can use the Patriot Act to collect a wide range of “sensitive records” -- including “firearms sales.”

Although there was nothing especially secret about using the Patriot Act to obtain such records — all business records, including firearms sales, are routinely subpoenaed during federal law enforcement investigations — the fact that they were specifically highlighted in the manual made a big impact with the NRA, Murphy said. “They were surprised,” she said. “It was like, ‘wow!”

Keene, the NRA leader, said the FBI training manual was especially disturbing because other federal laws require the destruction of records of gun purchases after they are used for a federally mandated background check. And it showed how federal agents can stretch their legal authorities to collect data on gun owners.

A spokesman for Director of National Intelligence James Clapper, who has taken the Obama administration lead in defending the surveillance program, declined comment about the NRA’s opposition to the NSA program. “We do not as a matter of policy, comment on matters under litigation,” said Michael Birmingham, a Clapper spokesman.

But Kristen Rand, legislative director of the Violence Policy Center, a leading gun control group, called the NRA’s stance self-serving. “Leave it to the NRA to exploit legitimate privacy concerns for their own purposes — stoking gun owners’ paranoia to raise money,” she said.

Under the so-called NSA “metadata” program, first disclosed last June by ex-contractor Edward Snowden, the agency has collected tens of millions of records on the time, duration and destination of every phone call in the country as part of a wide ranging and highly classified surveillance effort aimed at identifying potential terrorist threats. The agency has received the records from phone companies under secret orders by the Foreign Intelligence Surveillance Court (FISC) based on a provision of the U.S. Patriot Act that allows the FBI to collect “business records” deemed relevant to terrorist investigations.

Even before the NRA got involved, the NSA program was facing political trouble. An amendment brought by Reps. Justin Amash, R-Mich., and John Conyers, D-Mich., to pare back the program was defeated last July by just 12 votes in the House, 205 to 217.

Since then, the U.S. intelligence community has made a series of disclosures about “compliance” problems with the program, including a previously classified finding by a federal judge that U.S. intelligence misled the FISC about how the phone numbers were being used.

President Barack Obama, who has vigorously defended the NSA collection as “an important tool in our effort to disrupt terrorist plots,” last month named a five-member review panel to study the program and report back to him within 60 days.

In its friend of the court brief filed Sept. 4, the NRA argued that the NSA collection of all phone records, as well as other agency collection efforts revealed by Snowden, threatens NRA members’ s First Amendment rights.

“Under the programs revealed so far, the government may already possess information about everyone who has called the NRA by phone, emailed the NRA or visited the NRA’s website,” it wrote in the brief.

In addition, the brief states, the mass phone collection would make it easier for the government to create a nationwide “registry” of all gun owners.

“For example, a person whose phone records show a pattern of repeated calls to gun stores, shooting ranges, and the NRA, is considerably more likely to be a gun owner than a person who makes no such calls. If phone records are combined with other information, far more detailed profiles could be assembled,” it said.

Clapper, the intelligence director, and other administration officials have repeatedly said there are tight controls on the use of the NSA database of phone records and the records can only be accessed for terrorism investigations.

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