Charlie Neibergall / AP

For Hillary Clinton, gun control is a gift. To a Democrat who seems to inspire respect or resignation more often than enthusiasm, and to a candidate facing a challenge from the left, it’s the perfect wedge issue: She can appeal to Democrats who are fired up about strong regulation of firearms while also creating a contrast with Senator Bernie Sanders—and from the left, no less. Representing Vermont, a rural state with lots of gun owners, Sanders has been far more reluctant to back some gun-control measures.

On Tuesday, Clinton released this ad about gun control:

As Paul Waldman writes, Clinton seems to have realized that “the gun issue can actually benefit the Democratic presidential nominee. You’ll notice that the only policy position Clinton takes in the ad is, ‘we need to close the loopholes and support universal background checks.’ Universal background checks are supported by around 90 percent of Americans.”

One can think about gun regulation along two axes—how strong the laws are, and how enthusiastic the support for them is. Clinton isn’t proposing anything especially radical from a policy perspective, but she is trying to juice the enthusiasm, as she told a crowd in Iowa on Tuesday.

“We’re going to make this a voting issue just like the other side does,” she said. That’s a more succinct distillation of something President Obama said after the Umpqua Community College shooting. “I’d ask the American people to think about how they can get our government to change these laws, and to save lives, and to let young people grow up,” he said. “If you think this is a problem, then you should expect your elected officials to reflect your views.”

What would that kind of shift take?

In fact, it’s already the case that there are a good number of Americans who treat gun control as a central litmus test for political candidates. In a Gallup poll in October, 21 percent of voters said they would only vote for an office-seeker who sought stricter gun laws. Another 59 percent said stricter gun laws were one of several issues important to them. That’s a pretty big group.

On the other hand, twice as many people who support looser gun laws—40 percent—say they will only vote for a candidate who agrees with them.

Even if Clinton were able to double the number of single-issue pro-gun-control voters, it might not make any real dent in the nation’s gun laws. In part, that’s because Democrats tend to cluster in cities, where elected officeholders are already more likely to favor gun control. It’s also in part because the barriers to gun control don’t involve lack of rank-and-file political support—as Waldman’s 90 percent statistic attests. More important are things like conservatives’ distrust of liberals to enact modest controls that they agree with, and savvy lobbying work by the NRA. In the Democratic primary, however, that may be beside the point.

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