(CNN) - Sen. Dianne Feinstein on Sunday described the National Rifle Association as the biggest stumbling block to passing her assault weapons ban proposal.
"The NRA is venal. They come after you, they put together large amounts of money to defeat you," she said on CNN's "State of the Union." "They did this in '93, and they intend to continue it."
Feinstein on Thursday introduced details on a ban that would stop the sale, transfer, importation and manufacture of more than 100 specialty firearms and certain semiautomatic rifles. It would also limit the number of rounds in a magazine to 10.
The restrictions would not apply to guns owned before enactment of any law. Feinstein noted her proposal exempts from the ban more than 2,000 models used for hunting or sporting purposes.
In order for the proposal to go anywhere, Feinstein needs enough support from conservative Democrats, who will likely face intense lobbying from the NRA and other pro-gun groups.
While she recognized Sunday that passing the ban will be an "uphill fight" and the "hardest of the hard," she expressed confidence that she can at least get it to the Senate floor.
"There will be a package put together. If 'assault weapons' is left out of the package - and I'm a member of (the) Judiciary (committee), No. 2 in seniority - I've been assured by the majority leader I'll be able to do it as an amendment on the floor."
Feinstein helped push through the 1994 assault weapons ban that expired in 2004. She argued Sunday that the elementary school shooting in Newtown, Connecticut, last month was the tipping point in getting the ban reinstated.
"For me Sandy Hook was an epiphany," she told CNN's chief political correspondent Candy Crowley. "(The gunman) got a very powerful weapon. He went out with that weapon, and he killed 5- and 6- and 7-year-olds, I understand, with three to 11 bullets in each of their bodies, with a weapon that had the velocity of which could really rip these bodies apart. That should not be able to happen."
Vice President Joe Biden, who also helped champion the original assault weapons ban, expressed support for the ban on Thursday. Earlier this month, President Barack Obama announced that his legislative agenda to curb gun violence included a ban on assault weapons and a cap on magazine capacity.
Wayne LaPierre, executive vice president of the NRA, railed against Obama's inauguration speech, in which the president made a brief reiteration of his push for gun control.
"When absolutes are abandoned for principles, the U.S. Constitution becomes a blank slate for anyone's graffiti," LaPierre said in a speech Tuesday. "Words do have meaning, Mr. President. And those meanings are absolute, especially when it comes to our Bill of Rights."
Feinstein, however, said Sunday it boils down to one question: "Does government have an obligation to protect those children?"
"I believe we do," she continued. "I believe we do."
– CNN's Tom Cohen contributed to this report.
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