Gun-control, gun-rights groups ready for renewed debate after Colorado shooting

The extreme carnage at the Colorado movie theater, now one of the worst mass shootings in U.S. history, reopens the nation's passionate debate about gun control -- or gun rights -- and both sides were readying for renewed legislative efforts in the aftermath of Friday's shooting.

"We're going to see the gun control side talk about how more gun control is needed in wake of this horrible shooting," said John Velleco, director of federal affairs for of Gun Owners of America.

He added that gun-control advocates should acknowledge that "more gun control could actually make situations worse by making it harder for law-abiding folks to own and carry guns, which means for lunatics that there are more unarmed, potential victims."

Meanwhile, the Brady Campaign, the nation's largest citizens' lobby to prevent gun violence, pledged aggressive action.

"Today we are meeting with activists across this country as we continue to call on the American people to add their voice for change through our petition against arming dangerous people," President Dan Gross said in a statement Friday.

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"We are insistent that our elected leaders take action to prevent future tragedies. Political cowardice is not an excuse for evasion and inaction on this life-and-death issue," Gross said.

Gun-control advocates admit that any reform faces a difficult path in a sharply divided Congress -- on top of a presidential election year.

"I would hope we would see something in the Senate," Ladd Everitt, a spokesman for the Coalition to Stop Gun Violence, said about gun-control measures emerging from the Democrat-led chamber.

But the Republican-controlled House is a different story, he said.

"We don't live in a fantasy world and we understand that in the House it's a much tougher lift. The House has moved too far to the right that it's essentially a subsidiary of the NRA," or the National Rifle Association, he told CNN.