Known for his often blunt and colorful language, Panetta added that things can be done to protect children "so that the nuts that are out there won't use these kinds of weapons to wipe them out."
While the assault weapons ban is seen as having little if any chance of passage, support may coalesce behind requiring universal background checks, which is a top priority for advocacy groups that see it as the most important step to curbing gun crimes. The Brady Campaign to Prevent Gun Violence says 40 percent of gun sales are conducted with no criminal background checks, such as in some instances at gun shows or by private sellers over the Internet. Obama would seek to require checks for all sales.
Sen. Chuck Schumer, D-N.Y., already has sponsored a bill to require universal background checks that the Senate could take up, while Sen. Frank Lautenberg, D-N.J., has legislation banning ammunition magazines with more than 10 rounds.
Senate Majority Leader Harry Reid, D-Nev., a gun-rights backer who's been supported by the National Rifle Association in the past, responded cautiously, saying he was committed to ensuring the Senate considers legislation on gun violence early this year. He didn't endorse any of Obama's proposals.
Despite the uncertainty on Capitol Hill and opposition from the powerful NRA, outside groups are encouraged by polling showing public support for changes to the law. They intend to try to harness that sentiment to pressure lawmakers.
A lopsided 84 percent of Americans back broader background checks, according to a new Associated Press-GfK poll. Nearly 6 in 10 Americans want stricter gun laws, the same poll showed, with majorities favoring a nationwide ban on military-style weapons.
"Now it's up to us," said Dan Gross, president of the Brady Campaign. He said his group would be working "to bring that voice to bear in this process, because without that it's not going to happen."
AP White House Correspondent Julie Pace contributed to this report.
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