"This is our time. We need to pass bold, necessary and overdue gun control legislation. Iif we do not, this will happen again," she said referencing the shooting massacre in Newtown, Conn.
It's still unclear whether there will be enough support to pass new gun control laws.
The National Rifle Association had withheld comment on the murderous rampage until Tuesday.
"The National Rifle Association of America is made up of four million moms and dads, sons and daughters -- and we were shocked, saddened and heartbroken by the news of the horrific and senseless murders in Newtown," it said. "Out of respect for the families, and as a matter of common decency, we have given time for mourning, prayer and a full investigation of the facts before commenting. The NRA is prepared to offer meaningful contributions to help make sure this never happens again."
The NRA said it planned to hold a major news conference Friday.
In Pittsburgh, Dick's Sporting Goods said it is suspending sales of modern rifles nationwide because of the shooting. The company also said it will no longer display guns at its California stores.
Gun owners at Los Angeles stores are split over gun control laws.
"There is absolutely no merit in it," said Peter Stefansky, owner of Bain and Davis Gun Shop in San Gabriel. "Anybody who is crazy enough to want to harm somebody is going to find a way to do it."