Updated

Republican U.S. Senate candidate Kurt Bills on Friday refused to say whether he believes the allegations he levied against Democratic U.S. Sen. Amy Klobuchar in an ad are true.

Rather than answer the question from a Star Tribune reporter, he walked quickly to his car and drove away.

"Do you believe they are true?" he was repeatedly.

"I believe there's a lot to look into," Bills said. He denied a reporter's request to stop and answer a few questions as he left TPT's television studio.

On Thursday Bills ran his first ad, which claimed as Hennepin County Attorney Klobuchar covered up for Tom Petters in exchange for campaign donations. Petters was indicted in 2008 for his role in a Ponzi scheme that went back a decade. Bills' charge has been denied by Klobuchar as well as those involved in the Petters case, including by the court-appointed trustee in the case, who called the charge preposterous.

Mike Osskopp, Bills campaign manager, has said he does not know if the allegations Bills made in his ad are true.

Asked about the veracity of his charges, Bills on Friday only said that Klobuchar "took money from Tom Petters." Asked if he believes she covered up for him, which his ad alleged, he said "I believe Tom Petters was intimately involved in the Hennepin County office."

Klobuchar, like politicians of both parties including Republicans former U.S. Sen. Norm Coleman, former Gov. Tim Pawlenty and U.S. Rep. Michele Bachmann, all received campaign donations from Petters and his associates well before he in trouble with the law. She, like others, shed the money once he got in trouble.

Asked on TPT's Almanac whether he would run other ads, Bills said "we sure do hope so. I'd love to do a positive Kurt ad."

The ad has run once, during Thursday night's Vikings game. According to public records, the Bills campaign paid $15,000 to run it and canceled all his other ad time at the station.