Other states in which governors or lawmakers are calling for new restrictions include Arizona, California, Connecticut, Delaware, Florida, Illinois, Maryland and Oregon.
More proposals may emerge as legislative sessions in many states begin in coming weeks. In a recent letter to supporters, the NRA said state lawmakers "will soon be voting on dozens of new bills to impose greater restrictions on your right to own and use firearms." Andrew Arulanandam, a spokesman for the group, didn't respond to a telephone message seeking comment on the proposals.
Cerberus Capital Management, the New York-based owner of Freedom Group, the largest U.S. gunmaker, said last month that it isn't taking a position on gun-control debates and is moving to sell the company. Peter Duda, a spokesman for Cerberus at Weber Shandwick, a public relations firm, declined to comment further.
Republicans control a majority of governorships and state legislatures. Gun-control measures will be more difficult to pass in those states, said Andy Pelosi, the executive director of States United to Prevent Gun Violence, a New York-based firearms-control group.
"We're going to have to fight a very uphill battle, whether it's in Washington or state legislatures," he said.
Maryland Gov. Martin O'Malley, D, said Monday that he plans to propose limits on assault weapons and high- capacity magazines, as well as tougher licensing requirements for handguns. He predicted the measures will win approval.
"We know that it makes absolutely no sense, when you look at the level of carnage on our streets from guns, to blame everything but guns," he said in a speech at Johns Hopkins Bloomberg School of Public Health in Baltimore at the start of an academic conference on gun violence.
New York's Cuomo produced the most sweeping proposal. In Albany on Jan. 9, he said he wants to close loopholes in the state's assault weapon ban, forbid large-capacity magazines and allow the state to revoke gun licenses and confiscate weapons.