A super PAC supporting Sen. Thad Cochran (R-Miss.) released new commercials Friday slamming Cochran's primary opponent for hesitating when he was asked whether he'd have supported a Hurricane Katrina relief bill.

Mississippi Conservatives will air a television commercial and a radio ad each taking state Sen. Chris McDaniel (R) to task. The group will spend about $100,000 to run the spots, an adviser said.

"After Hurricane Katrina, Senator Cochran fought for us, pushing emergency relief funding through Congress," says the narrator of the 30-second TV ad. "But when trial lawyer Chris McDaniel was asked how he would have voted for Katrina, his response was, 'I don't know.'"

The minute-long companion radio spot criticizes McDaniel for the same remark.

In a recent interview with Politico, McDaniel declined to say definitively whether he would have voted for the 2005 relief bill. A McDaniel spokesman later told the publication that McDaniel would have voted yes.

The new ads come amid an escalating air war. The anti-tax Club for Growth, which is backing McDaniel, released an ad last week hitting Cochran for voting to raise the debt ceiling.

Cochran faces a potentially tough challenge from McDaniel. The senator got a new political headache this week when he received a low rating on the American Conservative Union's annual scorecard.

A McDaniel spokesperson didn't immediately respond to a request for comment on the new ads.

Meanwhile, the race took a new twist as Rep. Travis Childers (D) reportedly said he would run.