(CNN) - Arizona Sen. John McCain released two television ads Monday that continue to hammer home his opponent's past ties to a dubious company that aired infomercials promising viewers information about "hundreds of billions of dollars in government funding."
The company – National Grants Conferences – has been criticized by the attorneys general of multiple states for deceptive marketing and has an "F" rating from the Southeast Florida and Caribbean Better Business Bureau.
J.D. Hayworth, a former Arizona congressman, who appeared in one of NGC's infomercials in 2007, didn't shy away from his involvement with the company during an political roundtable broadcast live online last month.
"I always say about any product or service, one of the staples I learned growing up is 'caveat emptor' - 'buyer beware,'" Hayworth said. "I think that is a given in any commercial endeavor. I would certainly hope in this one."
The McCain ads call Hayworth a "lobbyist," "pork barrel spender," and "huckster," and offer another take on Hayworth's statement: "Voters beware."
"Congressman Hayworth helped a shady company rip people off, and was completely unrepentant when confronted with the facts," McCain's campaign communications director Brian Rogers said in a statement.
Hayworth spokesman Mark Sanders told CNN on Monday that Hayworth "said it was a mistake, that he should not have cut the ad and has apologized for it."
"What is truly shameful though is that Sen. McCain has no record to run on when it comes to what he's done for Arizona and is instead involved in character assassination of his opponent," Sanders said.
The Arizona Senate primaries will be held on August 24.
–CNN's Charles Riley contributed to this report