Crossroads super PACs fund $4.6 million campaign ad buys

American Crossroads and Crossroads GPS, two super PACs linked to former Bush adviser Karl Rove, announced plans on Wednesday to spend $4.6 million on a six-state ad blitz focused on competitive Senate races.

The groups, which have largely focused on opposing President Barack Obama's 2012 re-election campaign, are launching ads that target several of the most hotly-contested Senate races of 2012, as identified by Yahoo News.

American Crossroads is spending $2.6 million on television ads going after Democrats Bob Kerrey in Nebraska, Rep. Shelley Berkley in Nevada and Tim Kaine in Virginia. The commercials are specific to each candidate, hitting Kerrey, a former senator, on his record, Kaine on his ties to Obama and Berkley on ethics.

Crossroads GPS, which is not required to disclose its donor information, is running $2 million in ads against Sen. Claire McCaskill in Missouri, Heidi Heitkamp in North Dakota and Sen. Sherrod Brown in Ohio.

The ads begin airing Wednesday in state-specific media markets and will run for two weeks.

"We're turning up the heat on Washington to fix the debt mess and stop President Obama's destructive health care takeover," Nate Hodson, Crossroads GPS director of state and regional media relations, said in a statement. "These ads alert citizens to where policymakers stand and equip them to advocate for the practical solutions contained in the New Majority Agenda."

Democrats responded Wednesday to news of the ad buys by linking the Crossroads groups to special interests.

"Karl Rove is spending millions propping up George Allen, Rick Berg, Josh Mandel, and their fellow Republican Senate hopefuls because he knows these candidates will do the bidding for his special interest agenda in Washington," Matt Canter, spokesman for the Democratic Senatorial Campaign Committee said of the Virginia, North Dakota and Ohio Republican candidates in a statement. "He wouldn't be investing in these races if he didn't think he was going to get loyal votes for his reckless policies in return."