“This election is going to be won on the ground,” Chris Cox, the National Rifle Association’s top lobbyist, told me early last year as the gun lobby prepared to launch its all-out campaign to defeat Barack Obama. Historically, pro-gun voters have favored Republicans by a margin of 2- or 3-to-1, but that only matters if they vote. And, Cox stressed, millions of gun owners were not registered yet.

The NRA’s get-out-the-vote effort, its most ambitious ever, would target gun owners from all angles. Its field workers would register them at gun shows and gun shops in battleground states such as Florida, Ohio, and Virginia. The NRA spent millions on TV spots; one seven-figure ad buy last October attacked the president for “chipping away” at Second Amendment rights, urging Americans to “defend freedom.” Chuck Norris, a spokesman for the NRA’s Trigger the Vote campaign, warned apathetic gun owners, “I’ll come looking for the people who sat this election out.”

Mobilizing the NRA’s estimated 4 million members “is always a critical part of the equation for us on the Republican side,” says Charlie Black, a veteran GOP operative who was an adviser to Mitt Romney’s and Sen. John McCain’s presidential campaigns.

But 2012 was different: The NRA wasn’t simply reaching out to its core constituency—it was reeling in big checks from conservative funders eager to take advantage of its grassroots muscle. The arrangement was mutually beneficial: The NRA burnished its reputation as a political force to be reckoned with, while donors invested in the kind of all-out GOTV effort they had once expected from the Republican Party itself.

Overall, the NRA spent just north of $25 million on last year’s election: $7 million supporting Republican candidates, and $18 million attacking Democrats. This spending spree was boosted by the Supreme Court’s 2010 Citizens United ruling, which paved the way for activist groups to raise and spend unlimited amounts explicitly promoting or attacking candidates. The NRA also appealed to patrons who preferred to fly under the radar: The organization and its lobbying arm are both 501(c)(4) “social welfare” nonprofits and do not have to reveal their donors.

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