But this time, the issue that GOP strategists once relied on to provide crucial votes in close elections has lost much of its political punch.
The NRA may have become a victim of its own success.
Congress hasn't passed major legislation to restrict gun use in 14 years. Democrats -- scarred by past NRA campaigns -- almost never talk about the issue anymore.
And Americans now show little interest in gun control. Just half want tougher rules for gun sales, compared with nearly two-thirds in 2000.
"The issue has been essentially removed from the political agenda," said Robert Spitzer, a political scientist at the State University of New York in Cortland who has written extensively about the politics of gun control.
This marks a major victory for gun rights groups, which less than a decade ago were fending off demands from both Democrats and Republicans for strict new limits on gun ownership after the 1999 Columbine school shootings.
Yet that very triumph may prove politically perilous for Republicans hoping to put John McCain in the White House. Two years ago, GOP candidates backed by the NRA lost in a number of swing states, including Virginia, Missouri and Wisconsin, that could play pivotal roles this fall.
NRA leaders, who plan to spend millions on the presidential campaign, said they would be able to mobilize their members and bring key states into the GOP column Nov. 4.
"Voters have proven election after election that this issue is one of their first freedoms," NRA Executive Vice President and Chief Executive Wayne LaPierre said in a recent interview. "When people feel uncertain, when people feel unsafe, they run right back to the 2nd Amendment."
In 2000, the gun group converted that emotion into results. Tony Coelho, a former California congressman who managed Gore's presidential campaign, is among many analysts who think the NRA delivered the election for George W. Bush by highlighting Gore's endorsement of tougher gun laws. "It was critical," he said.
Coelho noted that had more gun owners voted for Gore in West Virginia, Tennessee or Arkansas -- all states targeted by the NRA -- he would have been president.
This year, gun rights groups see Obama's past positions on gun control as an equally inviting target.
When Obama was running for the Illinois state Senate in 1996, he appeared to endorse a ban on handguns. (He has since said that campaign aides incorrectly indicated that position on a candidate questionnaire and that he has never favored a ban.)
Obama voted against state legislation in 2001 and 2004 to ease restrictions on gun use. And in Washington, the senator opposed a 2005 bill to give gun manufacturers new protections from lawsuits.
He provided further ammunition for his critics in April with comments about "bitter" voters who "cling to guns or religion." Three weeks later in the Pennsylvania primary, Obama lost nearly two-thirds of voters from gun-owning households, according to exit polls.
The NRA has already begun attacking Obama in its magazines, a key medium for communicating with members. The group claims a membership of 4 million; critics say it is less.
"Right now, one of the most anti-gun politicians ever to set foot in Washington, D.C., may be just one election away from the Oval Office," NRA President John C. Sigler warned in the June issue of America's 1st Freedom, which also labeled Obama a "gun-ban elitist."
At the NRA's annual convention last month, Republican Party leaders, including McCain and former Bush strategist Karl Rove, echoed the NRA rhetoric, drawn from its well-thumbed political playbook that casts Democrats as foes of sportsmen and other gun owners.
But the new battle cries come at a time when the NRA has largely won the war.
At the state level, the NRA and its allies have significantly expanded the rights of gun owners. Forty states now meet the NRA's "right to carry" standard because they either don't require a concealed-weapon permit or allow people who meet minimal standards to carry a weapon. Two decades ago, there were just 10 such states, according to the group.
In Washington, the last major gun control bill passed in 1994, when lawmakers banned assault weapons and required background checks for handgun purchases.
Since then, gun rights groups helped block a renewal of the assault weapons ban. They successfully championed legislation to protect the gun industry from many product liability lawsuits. And they have consistently beaten back efforts to close the "gun show loophole," which allows those who buy guns from unlicensed dealers at gun shows to avoid the normally required criminal background checks.
This summer, the Supreme Court is widely expected to hand gun rights advocates another victory by striking down the District of Columbia's ban on handguns.
Meanwhile, Democrats have largely removed gun control from their political agenda. Many of the party's candidates now explicitly reject new gun restrictions and go out of their way to express support for gun rights.
Obama's campaign website notes that he "will protect the right of hunters and other law-abiding Americans to purchase, own, transport and use guns." It adds: "He also believes that the right is subject to reasonable and common-sense regulation."
When asked about gun control while campaigning in South Dakota recently, Obama replied: "What I believe is that there is a 2nd Amendment right. I think it is an individual right. I think people have the right to lawfully bear arms."
Obama's formulation is a marked contrast to Gore's campaign in 2000, when the vice president frequently boasted of having strengthened gun laws.
Gore and former New Jersey Sen. Bill Bradley, his Democratic primary opponent, frequently clashed over the issue in high-profile debates, each claiming to be more committed to cracking down on guns.
The NRA and its GOP allies have responded to Obama's defense of the 2nd Amendment with increasingly insistent warnings that it is a ruse. "Liberals in Washington often keep their real opinions to themselves," Senate Minority Leader Mitch McConnell (R-Ky.) told NRA members at their convention. "Don't be fooled."
If these cautions could once tip elections, recent history is not encouraging. NRA-backed U.S. Senate candidates in Pennsylvania, Montana, Missouri, Minnesota and Virginia all lost in 2006, even though the gun group spent more than $1 million on their races, according to federal election data collected by the Center for Responsive Politics.
In Wisconsin, another key swing state, the group spent nearly $700,000 to unseat the Democratic governor, who had twice vetoed legislation allowing state residents to carry concealed weapons. Gov. James E. Doyle cruised to reelection by 8 percentage points, and the leading champion of the pro-gun legislation in the state Senate lost his seat.
Even in the West, where guns have loomed mythically large on the political landscape, there are signs that the issue may be losing its potency.
Four years ago, in a race for Colorado's open U.S. Senate seat, Democrat Ken Salazar, who as state attorney general was a frequent advocate for tougher gun regulation, defeated a Republican who sat on the NRA board and benefited from more than $430,000 in independent expenditures by the group.