WASHINGTON — First came the letter-writing campaigns, then the protests at town hall meetings and now the television ads. The last several weeks in New Hampshire have had the feel of a heated electoral season — but the target of this siege, first-term Republican Sen. Kelly Ayotte, isn't on the ballot until 2016.
Welcome to Round 2 in the battle over gun control.
The first round ended last month, when a proposal to expand the background check system to cover most commercial gun sales fizzled in the Senate. Ayotte opposed the measure, as did 40 other Republicans and four Democrats, dealing a blow to the gun control movement animated by the December mass shooting at Sandy Hook Elementary School in Newtown, Conn.
Supporters of tougher gun laws vowed not to let the issue fade, as it has in the past. The vote, President Obama declared, was "just Round 1." But with the next election 18 months away and a Senate calendar already filled with immigration reform and the federal budget, the prospects for a renewed fight seemed dim.
Since the April 17 vote, however, the issue has shown unforeseen staying power.
Senate Majority Leader Harry Reid (D-Nev.) last week promised a vote on background checks "as soon as I can." Sen. Joe Manchin III, the West Virginia Democrat who worked with Sen. Patrick J. Toomey (R-Pa.) to draft a compromise, said he was seeking to win new support with "clarifications." He hopes for a vote before the August recess.
Background check supporters are counting on a two-pronged strategy: an aggressive campaign by advocacy groups to unnerve senators who might change their votes and delicate legislative maneuvering to create political cover for them.
Pressure to revisit the vote began to build when senators returned home for a weeklong recess in late April. Gun control groups, such as Mayors Against Illegal Guns and Americans for Responsible Solutions, dogged a few senators who had opposed the measure and disseminated polls showing steep drops in their approval ratings.
"The outside game is about convincing those who voted no that they've made the wrong choice. And that is happening. There are definitely second thoughts out there," said Jim Kessler, a gun policy expert at the centrist Democratic think tank Third Way. Senators who opposed the agreement, he said, "expected the politics to work for them after the vote and so far it hasn't."
Sen. Jeff Flake (R-Ariz.), who was heavily lobbied to support background checks, acknowledged on his Facebook page that his "no" vote probably caused his poll numbers to plunge, ranking him "somewhere just below pond scum."
On Thursday, Organizing for Action, a nonprofit group backing Obama's agenda, delivered a petition for a stronger background check system, with 1.4 million signatures, to lawmakers on Capitol Hill. Mayors Against Illegal Guns staged rallies in eight states over the weekend, delivering Mother's Day cards to senators urging them to side with mothers seeking to end gun violence.
The mayors group, co-founded by New York Mayor Michael R. Bloomberg, also dramatically escalated the air wars in New Hampshire, spending nearly $700,000 for two weeks of television ads battering Ayotte.
The squeeze on Ayotte has roused conservatives to her defense. American Future Fund, a conservative group that does not typically weigh in on gun matters, responded Friday with television ads supporting Ayotte. The weeklong buy cost about $200,000, according to a media tracking source.
The National Rifle Assn., which vigorously opposed the background check measure, has rallied around Ayotte as well, first in radio and television ads and then with a $25,000 television ad buy. The group is also starting a nationwide direct mail campaign aimed at members, with additional mailers sent to non-NRA households in select states, such as New Hampshire and Arizona.
Andrew Arulanandam, an NRA spokesman, dismissed the idea that the background check vote had triggered a backlash as "a manufactured issue by Bloomberg."
The relentless pressure by gun control groups could also harden opposition. In a fundraising email last week, Ayotte dug in and asked supporters for help. "I'm under attack for standing up for the U.S. Constitution by voting against flawed legislation that would have compromised our 2nd Amendment rights while doing nothing to prevent horrific tragedies such as Newtown," she wrote. "I won't back down."
Flake, also facing heat from advocacy groups, vehemently insisted last week that he remained opposed to the original background check measure. "They could change it," he said. "They could do a lot of things. But it wouldn't be the Toomey-Manchin proposal. I voted against that for a reason, and I'm not reconsidering my vote."
Manchin has suggested he was not open to significant revisions. "It's a pretty common-sense bill. I don't know how you make it any more common sense except redefine some areas," he said.
Supporters of the measure are optimistic that this back and forth is just political theater — a way for senators to lay the groundwork for changing their votes and avoiding the dreaded "flip-flopper" label.
"Clearly, this bill is going to have to look differently in order for members to face their constituents and explain why they changed their mind," said Sen. Christopher S. Murphy (D-Conn.). "There are a lot of ways that we can modify this bill without significantly weakening it."
Michael A. Memoli in the Washington bureau contributed to this report.