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NRA CEO Wayne LaPierre on Sunday challenged New York City Mayor Michael Bloomberg's plan to spend $12 million on ads meant to pressure senators into backing strict new gun control measures, saying Bloomberg "can't buy America."

Bloomberg's pro-gun control group Mayors Against Illegal Guns is launching the campaign in states where senators may be on the fence regarding a package of firearms proposals making its way to the Senate floor. As the push for that legislation appears to falter, President Obama plans to soon tour the country to talk about the need to reduce gun violence, a senior administration official confirmed to Fox News. Bloomberg also confirmed Sunday that he plans to spend $12 million to run ads in at least 10 states, suggesting there could be a political price to pay for opposing the measures.

Making clear he intends to be a counterweight to the NRA, Bloomberg said he wants to make sure the powerful gun lobby is not "the only voice" in this debate. If he can achieve that, Bloomberg said, "then I think my money would be well spent."

LaPierre bristled at Bloomberg's comments.

"He can't spend enough of his $27 billion to try to impose his will on the American public," LaPierre said Sunday on NBC's "Meet the Press." "He can't buy America."

Part of the purpose of the ad buy will be to rally support for comprehensive background checks.

LaPierre, though, said the existing system only serves as a "speed bump for the law-abiding" without catching the bad actors. LaPierre stressed that the NRA will continue to push for enhanced security in schools, better enforcement of existing federal gun laws, stricter penalties for straw purchases and illegal trafficking, and a system for making sure dealers can check gun purchases against a record of the mentally incompetent and dangerous.

"We're 5 million families. We're 80,000 law enforcement families. ... We want to make people safe. That's what the NRA does every day," LaPierre said.

Senate Majority Leader Harry Reid plans to include a universal background check provision in a gun control package he's preparing for the Senate floor. However, Republicans have so far been reluctant to back universal checks. Reid's office is leaving the door open for substituting the Democrat-backed measure with a compromise proposal, should one emerge.

At the same time, Reid announced this past week that a renewed ban on assault weapons and high-capacity magazines would not be in the main bill, though it would be voted on as an amendment.

Amid these hurdles, Bloomberg announced the ad buy Saturday. He said they were meant to bring the "voices of Americans -- who overwhelmingly support comprehensive and enforceable background checks -- into the discussion to move senators to immediately take action to prevent gun violence."

Bloomberg defended the ad buy Sunday , speaking on the same program as LaPierre, saying it would be a "great tragedy" if the momentum for gun control generated after the Newtown mass shooting withered. At the same time, Bloomberg said "I think we are going to win this."

We was blunt about the purpose of the ad buys. "We're trying to do everything we can to press upon the senators this is what the survivors want."

The two ads posted on the group's website, called "Responsible" and "Family," show a gun owner holding a rifle while sitting on the back of a pickup truck.

In one ad, the man says he'll defend the Second Amendment but adds "with rights come responsibilities." The ad then urges viewers to tell Congress to support background checks.

In the other ad, the man, a hunter, is shown with the rifle and children playing in the background.

"I believe in the Second Amendment, and I'll fight to protect it. But with rights come responsibilities," he says. "That's why I support comprehensive background checks."

The Senate is scheduled to debate federal gun control legislation next month. On March 28, the group plans for more than 100 events nationwide in support of passing gun control legislation that includes background checks.

Mayors Against Illegal Guns and other gun-control advocates frequently cite a mid-1990s study that suggests about 40 percent of U.S. gun transfers were conducted by private sellers not subject to federal background checks. Based on 2011 FBI data, the group estimates 6.6 million firearms transfers are made without a background check for the receiver.

A spokesman for Bloomberg could not immediately say if the $12 million was coming from Bloomberg or the mayor's political action committee, Independence USA. The New York Times, which first reported the ad campaign Saturday night, said Bloomberg was bankrolling the ad buy.

A spokesman for the National Rifle Association blasted Bloomberg and the new ads, saying NRA members and supporters would be calling senators directly and urging them to vote against proposed gun control legislation.

"What Michael Bloomberg is trying to do is ... intimidate senators into not listening to constituents and instead pledge their allegiance to him and his money," said spokesman Andrew Arulanandam.

Bloomberg has long supported efforts to curb gun violence, including sending New York City undercover investigators into other states to conduct straw purchases from dealers. Last month, Bloomberg's PAC poured more than $2 million into ads supporting Illinois state Rep. Robin Kelly, who won a special primary and ran partly on a platform of supporting tougher gun restrictions.

The new ads will air in states the group believes are divided on gun control. The ad campaign begins on Monday, sources told the New York Post.

The Senate is scheduled to debate federal gun control legislation next month after returning from the Easter Recess, which lasts from March 25 through April 5. On March 28, the group plans for more than 100 events nationwide in support of passing gun control legislation that includes background checks.

The Associated Press contributed to this report.

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