Gun-control advocates are hoping to reverse some of the political influence of the National Rifle Association and other gun rights proponents by urging the White House to strip the president’s next budget proposal of any provision that limits how federal agencies track firearms.

They are targeting one of the oldest tricks in the congressional playbook, a legislative sleight-of-hand that tucks little, sometimes random, changes to federal policy into massive “must pass” spending bills with the hope that they slip quietly under the radar and into law.

For years, the NRA and other gun rights groups have earned bipartisan support to amend spending bills with “riders” limiting how the Justice Department and the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) keep track of firearms.

Some of the provisions in question have been adopted in the president’s budget year after year, after having originated as legislative riders to spending bills on Capitol Hill.

But gun-control advocates are focusing on the practice as part of their broader strategy of confronting the NRA. President Obama’s 2014 budget proposal is scheduled to be released early next month, and the new focus on budgeting minutiae in the already emotional debate over the nation’s gun laws could create a flash point between Obama and his allies on the left.

How the NRA exerts influence over Congress

By raising the riders issue, liberals also hope to put the NRA on the defensive, forcing the group and its lobbyists to publicly defend the practice of attaching riders on appropriations bills, while also fighting off fresh legislation to limit gun violence introduced in the wake of the mass shooting at the Sandy Hook Elementary School in Newtown, Conn.

A new report, set for release Tuesday by the liberal Center for American Progress (CAP) and obtained by The Washington Post, highlights the decades-long practice of using riders to hamper ATF’s ability to police the flow of illegal weapons.

“The NRA often has this line, ‘Why don’t we enforce the laws on the books?,’ but for the last few decades they’ve been making it harder and harder for federal agencies to do that,” said CAP senior fellow Arkadi Gerney, the report’s co-author.

The report highlights six gun-related riders set for approval by the House and Senate this week as part of a short-term spending resolution. Four of the riders under consideration would be made permanent, while two would be renewed for another year. Most of the riders have been included in spending resolutions since at least 2004 with little debate and broad bipartisan support.

The riders considered most controversial by gun-control advocates bar the Justice Department from conducting inventories of federally licensed firearms dealers and block ATF from using data on firearms sales to draw conclusions about gun-related crime. Other restrictions prohibit ATF from revoking the license of a firearms dealer because of a lack of business activity, while three others focus on the definition and importation of antique firearms favored by collectors.

NRA spokesman Andrew Arula­nandam defended the NRA’s push for riders, noting that his group and many other organizations and industries similarly push to have riders added to appropriations bills.

“Given rules and regulations and congressional laws, we have to work within that framework to address it,” he said.

As Richard Feldman, a former NRA lobbyist who now leads the Independent Firearm Owners Association, put it: “There are lots of ways of skinning cats. It’s an old game on Capitol Hill. There are lots of ways for sophisticated professionals to play the game.”

Gun-related riders were included as part of the current spending package in talks that began last spring, according to House and Senate aides familiar with the discussions. The House approved its version of the spending plan over the summer, and senators agreed to include the riders in late November and early December — just days before the Newtown massacre.

But the riders “were not air-dropped in” after Newtown, said one aide, who was not authorized to speak publicly on the negotiations. “This did not appear at the last minute. This language has been around for eight years.”

But in light of the Newtown shooting, Gerney said he hopes his report might prompt Obama and lawmakers “to restart the clock, restart the debate, and look at each one of these things and say is it risky, is it worth it?”

A White House spokesman declined to say whether Obama’s budget request would include the riders.

Sen. Richard Blumenthal (D-Conn.), who has emerged as a leading voice on gun control since the shooting in his state, called the ban on gun-store inventories an “especially noxious and harmful” restriction.

“Inventories are important law enforcement tools to preclude the disguising or deceiving of illegal sales,” he said in an interview Monday.

Blumenthal, elected to the Senate in 2010, admitted he wasn’t familiar with the riders until after the Newtown massacre. Now, he plans to back a last-minute push by liberal Senate Democrats to block the gun-related riders and push Obama to strip them out of future budget requests.

“The world has changed since Newtown, and we have a better chance of eliminating them,” Blumenthal said. “The effort is very much a marathon, not a sprint, and we have to be prepared to fight session after session, Congress after Congress, to change this policy.”