(CNN) – The conservative super PAC Crossroads GPS is spending upwards of $4 million to air attack ads against Democrats in Florida, Montana, New Mexico and Ohio, the group announced Thursday.
The spot targeting Sen. Bill Nelson of Florida goes after the second term Democrat for voting "yes" on President Barack Obama's sweeping health care law, which the ad says created a "health care crisis" in the Sunshine State.
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"Tell Senator Nelson it's time to repeal," a narrator in the spot says.
Nelson faces four term U.S. Rep. Connie Mack in November's general election.
An ad running in Montana hits Sen. Jon Tester for not doing enough to reduce the federal debt, saying the debt was increasing "$3.5 billion every day since Jon Tester arrived in the U.S. Senate."
Rep. Denny Rehberg, a six term congressman representing Montana, is challenging Tester in the general election.
The Crossroads spot airing in New Mexico hits Rep. Martin Heinrich for supporting spending measures that Crossroads characterizes as superfluous. Heinrich is competing against former U.S. Rep. Heather Wilson to replace retiring Democratic Sen. Jeff Bingaman.
"Tell Martin more money wasted is not the solution," a narrator says. "Focus on jobs for New Mexico."
Sen. Sherrod Brown is the target of Crossroads' spot running in Ohio. The ad uses a mock movie trailer, a fake newscast and a pretend infomercial to blast Brown on his economic record.
Democrats currently have a 53-47 majority in the U.S. Senate, but are defending 23 of the 33 seats up for grabs in November. That includes 21 Democrats and two independents who caucus with the party.
"Karl Rove is spending millions propping up Denny Rehberg, Josh Mandel, Connie Mack, and Heather Wilson because he knows that these Republicans will be rubber stamps for his agenda that puts Wall Street, Big Oil, and millionaires ahead of seniors, small businesses, and the middle-class," Shripal Shah, press secretary for the Democratic Senatorial Campaign Committee, wrote in a statement responding to the ads. "As voters learn more about these dangerous, anti-middle class policies, they'll quickly realize that they can't afford to send Republicans who support this agenda to the Senate."
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