Politicians don’t usually confess to letting polls dictate policy, but two weeks after President Obama said the American people would decide the fate of gun control, he announced a legislative push for tougher, universal background checks, a limit on high-capacity magazines, and a ban on assault weapons. All three measures do, in fact, command majority support in public-opinion surveys. But that Abraham Lincoln adage invoked recently by Obama—"with public opinion there is nothing you can’t do, and without public opinion there is very little you can get done in this town"—might not hold true here: congressional Republicans, not the American public, are likely to have the final say.

Universal background checks command overwhelming bipartisan support, with as many as 90 percent of voters in support of closing the gun show loophole and other, more thorough background checks. Banning assault weapons and high-capacity magazines is more controversial. While every survey conducted since Newtown shows majority support for the latter, most surveys show Republicans remaining opposed. Support for an assault weapons ban is even more tenuous, with several post-Newtown surveys showing the public narrowly opposing a ban on semi-automatic weapons and Republicans opposed in every poll.

But gun control advocates have reason to be somewhat optimistic. A wave of recent surveys suggests that support for an assault weapons ban, which spiked right after Newtown, has risen further. Every poll conducted in January shows majority support for such a ban—as high as 56 percent in a Pew Research survey, up from 44 percent in their first poll after Sandy Hook. Other surveys have hinted at a similar trend, bucking the assumption that gun-control support peaks immediately after a mass shooting. With gun-control advocates currently dominating the debate—with an assist from the NRA's inept PR department—that trend could continue. But that would require Republican converts, and the president's high-profile announcement today might not make Republican voters more inclined to support new gun control measures, especially as the debate becomes increasingly partisan in Congress.

The aforementioned bans won't make it through the House of Representatives without the support of the Republican rank-and-file. The majority of House representatives hold “A” ratings from the NRA, and opponents of gun control are more mobilized than advocates. Pew Research found that 42 percent of the former, versus 25 percent of the latter, have participated in some sort of political activity to promote their views on gun policy. What's more, 23 percent of gun rights supporters have given money to an organization that advances their cause, compared to just 5 percent of gun control supporters. Given that these gun right supporters are overwhelmingly Republican, it’s not hard to see why Sen. Harry Reid has dismissed the chances of gun control passing the House. Boehner could ignore the Hastert rule, again, by bringing gun-control legislation to a vote without majority support from his caucus, but the result of inaction here is not an across-the-board tax increase ("fiscal cliff") or furious northeastern Republicans (Hurricane Sandy relief). Even if Boehner did adhere to the non-binding rule, it’s unclear whether the legislation has 60 votes in the Senate, where Republican cross-overs will be necessary to break a filibuster and compensate for an unknown number of red state Democratic defections.

If indeed public opinion decided the issue of gun control, Obama's plan would get through Congress and land back on his desk. But the more ambitious elements of his proposal don't hold the support of a majority of Republican voters, which means it almost certainly won't be supported by all of those congressional Republicans who hail from safe districts and have shown, time and again, that they are not concerned by national public opinion. A majority may want to ban assault weapons, but not as fiercely as the minority wants to prevent one.