(CBS News)-- Late this morning, lawmakers will announce the introduction of the first gun control legislation to be put forth in Congress since the massacre in Newtown, Connecticut that left 20 children and six adults dead. The move comes as gun control advocates say the political environment is more favorable for new gun control laws than it has been in years.
But at least when it comes to the most ambitious item in the legislation, and on President Obama's gun control agenda - a reinstatement of the ban on assault weapons - advocates have little reason to be optimistic.
Sen. Dianne Feinstein, D-Calif., Rep. Carolyn McCarthy, D-N.Y., and five other Democratic lawmakers will be joined by mayors, law enforcement officials and gun violence victims at 11:00 a.m. ET to unveil a measure that would reinstate the assault weapons ban, which went into effect in 1994 bill and lapsed in 2004. The bill would outlaw the sale, importation and manufacture of over 100 specialty firearms along with certain semiautomatic weapons; it would also outlaw the sale, importation and manufacture of ammunition magazines that accept more than 10 rounds. Americans would be able to keep affected weapons if the weapons were already in their possession when the bill was enacted, and exemptions would be made for specific hunting and sporting weapons, as well as antique or disabled weapons.
Mr. Obama called on Congress to pass the assault weapons and high-capacity magazine ban on Jan. 16, as well as a requirement for universal background checks for gun sales and other measures. Citing the horrific Newtown massacre one month earlier, the president said that "if there's even one thing we can do to reduce this violence, if there's even one life that can be saved, then we've got an obligation to try."
The White House opted not to send its own bill to Capitol Hill after Mr. Obama's announcement; it says it supports Feinstein's effort and has worked with her office in crafting the new version. Yet there is little reason to believe that the measure could pass the GOP-led House - and it may well not even be able to get through the Democrat-led Senate.
While gun control opponents were muted in the days after the Newtown attack - and some previously anti-gun control lawmakers have showed openness to some new laws - the rhetoric soon turned harsh. The National Rifle Association has gone on the offensive, unleashing its lobbying muscle against the new push and deeming the president an "elitist hypocrite" in an ad last week. The top Republican in the Senate, Minority Leader Mitch McConnell, R-Ky., sent an email to donors to his reelection campaign in which campaign manager Jesse Benton wrote that "[t]he gun-grabbers in the Senate are about to launch an all-out-assault on the Second Amendment. On your rights. On your freedom." Many Republicans in the House and Senate reacted angrily to Mr. Obama's proposals, with Rep. Tim Huelskamp, R-Mich., saying that "[t]he right to bear arms is a right, despite Mr. Obama's disdain for the Second Amendment and the Constitution's limits on his power."
Democrats control 55 out of 100 votes in the Senate, and barring a significant change to the filibuster rule, supporters of the gun control measure would need all of those votes -- plus five Republican votes -- to pass the bill. That's a tall order: At least five Senate Democrats have declined to take a position on the president's proposal, and there is only one Republican in the Senate - Mark Kirk of Illinois - who supports an assault weapons ban.
Senate Majority Leader Harry Reid, D-Nev., indicated recently that he wouldn't even allow a vote on an assault weapons ban, since it would not pass the GOP-led House. (A vote for gun control could be political damaging to Democrats from gun-friendly states, some of whom are up for reelection in 2014.) On Tuesday, Reid signaled that he may allow a vote, though he made clear that he did not expect the measure to pass. The Senate Majority Leader, a longtime supporter of gun rights, said he expected the Senate Judiciary Committee to produce a bill after its hearings on gun control, which begin next week.
"It may not be everything everyone wants," he told reporters. "But I hope it has stuff that is really important."
Rep. Peter King, R-N.Y., is the only Republican in the House who has signaled an openness to an assault weapons ban; a handful of other Republicans have said they are open to some gun control measures, though many have pushed a focus on mental health and enforcing existing laws. Feinstein's bill may be used to give lawmakers from gun-friendly states a measure to oppose before they support the less ambitious bill that comes out of the Judiciary Committee.
On January 17 - the day after Mr. Obama announced his proposals - CBS News White House correspondent Major Garrett pressed the White House on its decision to back Feinstein's bill. He spokesman Jay Carney if the White House fears "that if you put everything in there with the assault weapons ban, that could pull it down and that you have a better chance of achieving some of these other goals if they're adjudicated, if you will, in Congress separately?"
"I can't speak to that directly," Carney responded. "I just know that we are working with Sen. Feinstein, working with other senators in the Senate, and we'll work with House members to try to move something forward here. The reality is, as we've talked about, that none of this is going to be easy. But the fact that it's not easy doesn't mean we shouldn't try." Vice President Joe Biden, who led the effort to craft Mr. Obama's proposals, is hosting a "fireside hangout" on Google+ Thursday to discuss gun control efforts.
The most likely of Mr. Obama's major gun control proposals to win passage in Congress appears to be universal background checks, which a CBS News/New York Times poll last week found is supported by nine in 10 Americans. In the same poll, more than three in four Americans said they favor creation of a national database to track all gun sales in the United States. A ban on high-capacity magazines was backed by 63 percent of Americans; 53 percent backed an assault weapons ban.
Asked if he could point to evidence that the assault weapons ban had a chance for passage, Rep. Carolyn McCarthy's communications director, Shams Tarek, said there is a better environment for passage of new gun control legislation than at any time since the Clinton administration.
"Is it tough? Of course it's tough," he said. "But we're hopeful."
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