Though John McCain vowed that attacks on Barack Obama at his campaign events "will never happen again," the Republican presidential candidate says he's concerned he may be unable to control all of his supporters -- especially third party groups.
At a rally in Cincinnati Tuesday, McCain denounced the remarks of local radio talk show host Bill Cunningham, who introduced the candidate with several attacks on Obama, including suggesting he is a "hack" who would sit down for tea with Iranian President Mahmoud Ahmadinejad and Hezbollah terror leaders.
Cunningham also called Obama by his full name, Barack Hussein Obama, during the on-stage introduction. McCain immediately denounced the remarks and promised a civil debate should Obama become the Democratic presidential nominee.
But speaking to reporters aboard his campaign tour bus late Tuesday, McCain acknowledged that conservative independent groups pursuing a similar line to Cunningham's could be impossible to control.
"I think you have to worry about that, particularly the 527s," McCain said, referring to the independent advocacy groups that are not subject to contributor limits.
"We're aware of many of the things that 527s have done ... where unlimited amounts of money can pour into negative campaigns such as we saw against John Kerry and his combat record, as we saw against (former Georgia Sen.) Max Cleland ... they're really very not accountable to anyone. At least I have to say 'I'm John McCain and I approve this message.'"
Some critics blame his signature campaign finance reform legislation, co-sponsored with Wisconsin Democratic Sen. Russ Feingold, for the explosion of uncontrolled 527 groups. But, McCain said the law is not the problem and argued that 527 groups were able to sprout up as a result of loophole in a 1974 campaign finance law.
McCain said he would do his best to prevent dirty politicking by his campaign and surrogates.
"The moral of the story is we just have to have stronger control of our campaign. ... There is no excuse for what happened today," he said, adding that his campaign has plans to expand its bare bones staff.
Cunningham says he was told by party officials to give the audience red meat to warm up the crowd that came to see McCain. He says he did and the crowd loved it, but McCain then threw him under the bus. Cunningham says McCain has now lost his support.
"I'm gonna follow the lead of Ann Coulter. I've had it with John McCain," Cunningham told FOX News' "Hannity & Colmes."
"I'm going to endorse Hillary Rodham Clinton for president because she would do a better job in the Oval Office, I think, than the liberal John McCain. I'm done with him."
Cunningham said McCain "embarrassed himself," and then made up a name of his own for the Arizona senator, "John Juan Pablo McCain," an apparent reference to McCain's sponsorship of immigration reform legislation. He added that McCain should be "repudiating Democrats and leaving conservatives alone."
Meanwhile, as McCain preaches civility, his own campaign put out a call to Obama's camp to call off Democratic National Committee Chairman Howard Dean, who has been attacking McCain for choosing to forgo public campaign financing.
"Howard Dean and the Democratic National Committee leadership have launched a personal and negative assault on Senator McCain's character. Howard Dean himself questioned Senator McCain's integrity, and a DNC official called McCain a liar," said Communications Director Jill Hazelbaker.
"We agree with the Obama campaign's statement today that this debate should be respectful and focused on issues, and it would be encouraging to see Senator Obama denounce the character attacks coming from the leadership of his party."
FOX News' Mosheh Oinounou contributed to this report.