To be sure, the gun control debate sparked by the killing of 26 children and school staff in Newtown, Conn., on Dec. 14 has largely been framed by the battle between entrenched lobbying groups, such as the Brady Center and the National Rifle Association.
But key to those efforts, political experts say, is grassroots support on both sides. Obama's coalition is trying to tap into the fact that, according to polls, support for gun control jumped nearly 20 percent in the wake of the Newtown massacre, where a majority of Americans now support measures such as an assault wapons ban and expanded background checks.
Gun rights activists, however, say they have the momentum on their side, pointing to increased NRA memberships since the December massacre, and vowed to demonstrate that momentum on Saturday.
Gun control advocates in the media "have created this echo chamber where they're convinced they've succeeded in exploiting this tragedy and produced a national change in public opinion," says Michael Hammond, the legislative consultant for Gun Owners of America in Springfield, Va. "But we don't see it."
"I think the question of whether we have a reinvigorated gun control movement will depend on whether [gun control advocates, including Obama] can come out of this with a negotiated victory," adds Mr. Hammond. "That's why it's so incredibly important that Republicans stand firm. This is a seminal battle perhaps of our times."