"If this doesn't do it," he asked, "what is going to?"
Such pleas have become near rituals for Bloomberg, a billionaire who has used both his mayoralty and his own money to push the gun-control cause only to see it slide from the national agenda again and again. But Bloomberg is pressing to make this moment a turning point, even as the political calculus around the issue remains hard to solve and he faces questions about a big-city mayor's sway with often-rural opponents.
During his 11 years in office, Bloomberg's administration has conducted stings and filed lawsuits to expose what it said were out-of-state dealers flouting gun sale laws. He and Boston Mayor Thomas Menino founded and run a 700-member mayors' group that lobbies lawmakers on gun measures.
Bloomberg's multimillion-dollar political pocketbook has backed like-minded candidates and attacked adversaries in races around the nation, and he criticized both Obama and Republican nominee Mitt Romney for not making the issue more of a priority during this year's presidential campaign. Bloomberg ultimately endorsed Obama.
The mayor has repeatedly stood with victims' families and spoken out tartly after mass shootings. After 12 people were killed and dozens of others wounded in a shooting this summer in a movie theater in Aurora, Colo., Bloomberg wondered aloud why police officers across the country didn't threaten to strike until tougher gun laws were passed. He later clarified that he didn't mean that literally, noting that New York law prevents police from striking.
Bloomberg's efforts have delighted gun-control advocates, but they've engendered pushback - sometimes taunting - from gun manufacturers, sellers and some state officials.
Gun-rights advocates have sometimes portrayed Bloomberg's initiatives as grandstanding by a politician who wants to build a national profile. And on Sunday, New York Times columnist David Brooks questioned whether the Manhattan-dwelling mayor could be an effective champion for his cause.
"It's counterproductive to have him as the spokesperson for the gun law movement," as it's already "perceived as an attack on the lifestyle of rural people by urban people," Brooks said on NBC's "Meet the Press," where the mayor had just appeared.
Bloomberg said Monday that it was indeed his place to speak: "I'm a human being," as well as the mayor of the nation's largest city - one that's on track this year to logs its lowest murder rate since record-keeping began in the 1960s, he said.
"I'm going to fight, and you should fight, as well. ... This is an outrage. We are killing each other," he said.
Bloomberg and the mayors' group he leads, Mayors Against Illegal Guns, are calling for reinstituting a version of the federal assault weapons ban that expired in 2004, closing the so-called "gun show loophole" by requiring all gun sellers to conduct criminal background checks on prospective buyers, and stepping up federal prosecutions of people who lie on background checks, among other proposals.
The group - a nonprofit financed by Bloomberg and other donors - released 34 video statements Monday from shooting survivors and victims' relatives around the country. John Feinblatt, Bloomberg's top aide on gun issues, said the videos had been scheduled to come out this week, but the group made sure of it by editing the pieces Friday after the shootings in Newtown, Conn. Twenty-year-old Adam Lanza killed his mother at their home, 20 children and six adults at Sandy Hook Elementary School, and then himself.
"A tragedy like this is often what brings the public to pay attention to an issue and brings Capitol Hill's attention to this issue," Feinblatt said, but "we never stop paying attention to this issue."
Proposals to stiffen gun laws have met potent opposition in Washington in recent years. But at least one Republican lawmaker has joined Democrats - including Sen. Joe Manchin, an avid hunter and lifelong member of the National Rifle Association - in saying it's time to discuss gun regulation again.
In New York, meanwhile, Democratic Gov. Andrew Cuomo said Monday that he would propose state gun laws to close loopholes related to assault weapons, though he didn't give specifics.
Robyn Thomas, executive director of the San Francisco-based Law Center to Prevent Gun Violence, thinks Bloomberg's efforts will make a difference.
"I do think he's ready to put a lot into this in a way that will get attention, finally," she said.
But Bob Levy, the chairman of the board of the libertarian Cato Institute, said key pieces of Bloomberg's agenda - the background check and assault weapons ban proposals - could face a difficult legal road. Levy pointed to a federal appeals court decision last week that struck down a ban on carrying concealed weapons in Illinois, saying the state hadn't done enough to show the law was justified by an increase in public safety.
Chris Foye, for one, gives Bloomberg credit for seizing the moment to speak up about guns.
"Every little bit helps," said Foye, whose 13-year-old son, Chris Owens, was killed by a stray bullet in Harlem in 2009. "For us to sit back and ignore it, that would be the worst tragedy ever."
Associated Press writers Eileen AJ Connelly in New York and Michael Virtanen in Albany, N.Y., contributed to this report.
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