* Gun lobby shows enduring clout in fighting expanded background checks
* Gun-control groups aim to use similar playbook in fighting back
* Targeting some Democrats could backfire
* A matter of "intensity versus preference"
As lawmakers gathered in the U.S. Senate on Wednesday to vote on a plan to expand background checks for gun buyers, staffers in the office of Alaska Democratic Senator Mark Begich fielded a steady stream of calls urging him to break with his party and vote against the measure.
Those callers got what they wanted: Begich voted no - one of four Democrats from gun-friendly states to do so - and the most ambitious gun-control push in two decades went down to defeat.
It was an impressive show of force by the National Rifle Association, which reaffirmed its reputation as one of Washington's most powerful interest groups by turning back one of President Barack Obama's top second-term priorities.
The NRA mobilized a disciplined, grassroots army that flooded Republican and conservative Democratic lawmakers' offices with phone calls and e-mails.
The NRA and its supporters also followed a tightly woven script that accused Obama of not following up on thousands of gun buyers each year who fail background checks under existing laws. The association's talking points, often repeated word for word by lawmakers and NRA supporters, cast the new background checks plan as an infringement on the constitutional right to bear arms of law-abiding citizens.
After the measure fell six votes short of the 60 votes it needed to advance in the 100-member Senate, Obama acknowledged that gun-control supporters have a way to go before they can match the sustained passion that has allowed the gun lobby to steadily loosen firearms laws over the past 18 years.
Now, with the push for gun control in a holding pattern on Capitol Hill, gun-control groups are vowing to meet Obama's challenge to beat the NRA at its own game.
Gun control has a deep-pocketed sponsor in New York City Mayor Michael Bloomberg, who spent $12 million on ads in March targeting key lawmakers.
Organizing for America, an advocacy group spawned from Obama's re-election campaign, plans to mount rallies to pressure lawmakers who voted against the bill.
Separately, the Progressive Change Campaign Committee, an independent liberal group, plans to run newspaper ads criticizing Montana Democratic Senator Max Baucus for voting against the bill, the first of what the group says could be many targeted pressure campaigns aimed at lawmakers who will face re-election next year.
That effort could backfire, analysts say.
The Democratic Party - which controls 55 seats in the Senate - needs conservative Democrats such as Begich and Baucus to win re-election next year in order to retain control of the chamber. Efforts to punish them for their vote could hand those seats to Republicans.
Going after Begich or Baucus would "blow up in their face," said Jim Manley, a former spokesman for Senate Democratic Leader Harry Reid. "They have to decide whether they want an issue or whether they want to win."
INTENSITY TRUMPS POPULARITY
As Wednesday's vote showed, the NRA can count on their 4.5 million members to leap into action when it counts. Gun-control groups have yet to match that type of enduring intensity.
"People who own guns care about guns," said Richard Feldman, a former NRA lobbyist who now heads a gun-rights group called Independent Firearm Owners of America that supported the background-check legislation.
"People who don't own guns, they have the same vote but they don't care about guns," he said.
Wednesday's vote was the NRA's toughest test in nearly 20 years.
The December massacre of 20 school children and six adults in Newtown, Connecticut, pushed gun control to the top of Obama's agenda and galvanized advocates such as Bloomberg.
The NRA also was coming off an election that called its influence into question. Only 5 percent of the $19 million the group spent on television ads and other forms of electoral communication in 2012 went toward winning candidates, according to the Center for Responsive Politics, which tracks political spending.
Demographic trends are working against the NRA as well. Fewer than one-third of U.S. households owned guns in 2011, down from 54 percent in 1977, according to the University of Chicago's General Social Survey.
The NRA's stance against expanding background checks to people who buy guns over the Internet and at gun shows, reversing its earlier support, put the NRA at odds with 80 percent to 90 percent of the public.
But as Wednesday's vote showed, a motivated minority that cares passionately about an issue often carries more weight in Washington than a majority that is not quite as focused on that single issue.
"It's intensity versus preference," said anti-tax activist Grover Norquist, a member of the NRA's board of directors. "While 90 percent will tell you, 'Sure, I'm for that,' 5 percent will really hate that, and on Election Day the only people who remember your position are the 5" percent, he said.
Gun-control advocates could make headway in the coming months by making enough noise at the grassroots level to let lawmakers such as Baucus and Begich know that they would not pay a significant price if they changed their minds, said Matt Bennett, a co-founder of the centrist Democratic think tank Third Way.
That could allow the bill to come back up for another vote before the 2014 elections, he said.
"Showing a bit of anger is useful," Bennett said.
Perhaps, but after this week's vote, Baucus, for one, made clear that he believed that rural Montana voters would punish him if he supported a measure seen as limiting gun owners' rights.
Gun-control groups will have to match an NRA political machine that maintains a vigorous presence at all levels of government. In February alone, the group donated to three state legislature candidates in Rhode Island and 16 congressional candidates and campaign groups, according to federal records.
Despite the NRA's setbacks in last year's elections, the gun lobby's tactics and legislative success remain an imposing force, said Sheila Krumholz, executive director of the Center for Responsive Politics.
Gun-rights groups have donated $596,000 to the sitting members of the Senate since 2007, while gun-control groups have donated only $5,000.
The NRA and other gun-rights groups "are perennially among the most powerful interest groups in Washington," Krumholz said.