Gun control has rarely been a winning general election issue for Democrats — and they know it. But the renewed focus on homeland security after the terror attacks in Paris and two mass shootings at home has given Democrats an opening to try to make it one.

Democratic challengers in some of this year’s most competitive races are appealing to Americans’ fears about terrorism to broach gun control, specifically by calling out Republican incumbents for not backing New York Republican Rep. Peter T. King’s bill, first introduced nine years ago, to prevent people on the terror watch list from purchasing firearms.

“It’s an easier issue to talk about because it seems so obvious and logical,” a Democratic Congressional Campaign Committee aide said on Dec. 4.

Last week, as lawmakers were debating unrelated pieces of legislation, Democrats repeatedly tried to force votes on the King bill. Not one Republican opted to halt floor proceedings to consider the bill — not even King himself. Republicans rarely side with Democrats when the minority party tries to alter floor proceedings.

But with Minority Leader Nancy Pelosi calling it a key vote, Democrats inside and outside of Congress have seized on Republicans’ refusal to bring up the measure for their own messaging on the security issue.

One Washington, D.C., Republican operative acknowledged that some in the party “kinda walked into a punch” in opposing the King legislation. But, “at the end of the day, national security is what this election is turning into, and that’s a winning issue for Republicans.”

The issue emerged after the terror attacks in Paris and intensified after the Dec. 2 shootings in San Bernardino, Calif.

• Colorado Democratic state Rep. Morgan Carroll attacked Rep. Mike Coffman, whom she’s challenging in the 6th District.
• Two Democrats hoping to challenge Rep. Martha McSally in Arizona’s 2nd District, the seat once held by former Rep. Gabrielle Giffords, blasted the freshman Republican for blocking King’s bill, with candidate Matt Heinz saying, “ McSally’s pact with the NRA is a ticking terrorist time-bomb.”
• In Nevada’s 4th District, Democrats Susie Lee and state Sen. Ruben Kihuen hit vulnerable GOP Rep. Cresent Hardy.
• In New Jersey’s 5th District, Democrat Josh Gottheimer called on GOP Rep. Scott Garrett to support the legislation.
• In New York’s 1st District Anna Throne-Holst knocked Rep. Lee Zeldin for blocking the bill on Thursday.

“You’ll notice it’s not every Democrat making an issue out of this issue — because there’s not one size fits all,” the DCCC aide said. But she said the range of districts, from Long Island to Colorado, underscores that Democratic vocalism on the issue isn’t just a geographic phenomenon.

The day after the California shootings, the Senate rejected, 45-54, an amendment similar to King’s bill. Vulnerable Sen. Mark S. Kirk was the only Republican joining Democrats in support of the measure, and North Dakota Democratic Sen. Heidi Heitkamp, who is not up for re-election until 2018, voting against it.

Mass shootings in the past haven’t spurred much political action. Even after the massacre of schoolchildren in Newtown, Conn., legislation that would have tightened background checks and closed the gun-show loophole went nowhere. In the following year’s midterm elections, gun control was barely mentioned as Democrats lost the Senate and lost ground in the House.

Similar legislation was reintroduced on Dec. 3, but it failed, 50-48, even with four Republicans voting for it. The cycle’s second-most vulnerable senator, Wisconsin Republican Ron Johnson, did not vote.

Democrats in competitive districts have been reluctant to make gun control a central part of their campaigns.

Part of the reason, Democrat strategists say, is that it is not clear that gun safety is an issue their base votes on. Gun rights supporters, however, often make it their singular issue, Democrats say.

Besides — gun control (or “gun safety,” as some advocates prefer to brand the message), is a nuanced issue, even among Democrats.

“There are a lot of Democrats who want background checks but not full gun control, so you have that middle,” veteran Democratic strategist Achim Bergmann said

Of course, any gun control legislation runs into the powerful National Rifle Association.

“In the past, Democrats have gotten real skittish about the NRA coming in and spending a lot of money against them,” Bergmann said.

Gun control will likely continue to be a wedge issue in Democratic primaries, Bergmann said. In Nevada’s 4th District, for example, where four Democrats are challenging Hardy, California’s shooting pressured one Democrat to drop his NRA membership.

“I cannot continue to be a member while the NRA refuses to back closing loopholes that allow the mentally ill, criminals, and terrorists to buy guns in this country,” former state Assemblyman John Oceguera emailed his supporters.

And in Maryland’s Senate primary, Rep. Donna Edwards has accused Rep. Chris Van Hollen of doing the NRA’s bidding by exempting the organization from disclosure requirements in a 2006 campaign finance bill. Van Hollen responded with an ad affirming his opposition to the group.

Just because Democrats have found an angle to make gun control an issue, that doesn’t mean they’ll look try to make it a bigger one.

“It’ll be a case-by-case basis where people use gun control beyond this bill in their campaigns,” the DCCC aide said.

But Adrianne Marsh, a Democratic consultant who has worked on races in Montana, Colorado and Missouri — states in which gun ownership is part of the culture — acknowledged that while Democrats have had a tough time making guns a winning issue, they have won on other issues that were once just as divisive.

Emma Dumain contributed to this report.

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