WASHINGTON -- Sen. John McCain (R-Ariz.) is a longtime critic of the Supreme Court's decision in Citizens United, which removed corporate limits on political spending and led to the rise of super PACs. But on Tuesday, he criticized the decision at a "storm relief" event in Bowling Green, Ohio, with Republican U.S. Senate candidate Josh Mandel, who has been a huge beneficiary of the spending.

"I think it's been a disaster," McCain said to reporters in answering a question on the decision, according to the Toledo Blade. "There is money coming in from places we never knew where it came from. And I guarantee you there will be scandals ... and corruption, and then there will be reform."

The candidate he appeared with, however, has benefitted from $18 million in outside spending, according to the Center for Responsive Politics. His opponent, Sen. Sherrod Brown (D-Ohio), has had about $12.6 million in outside help. The Karl Rove-linked Crossroads GPS has boosted Mandel by $6.3 million, in addition to his $4.3 million from the U.S. Chamber of Commerce and over $1 million from the National Federation of Independent Business, none of which are required to disclose their donors. Brown has had millions more spent against him in issue ads, which are not counted in Federal Election Commission data compiled by CRP.

Brown's campaign said it agreed with McCain. "With Josh Mandel's opposition to the auto rescue that helped protect 850,000 Ohio jobs, the only way his embarrassing campaign has remained competitive is with more than $30 million in secretly funded outside spending backing him, and I agree with Senator McCain that reform is needed to avoid scandal and corruption in the process that's keeping Josh Mandel afloat," Brown spokesman Justin Barasky told HuffPost.

Despite the onslaught of spending, Brown has an edge, according to recent polls. The Huffington Post's Pollster shows him leading Mandel by a 49.4-42.9 margin.

McCain has dubbed the 2010 ruling the "worst decision ever" and has previously predicted scandals from it. The ruling dismantled many of the regulations he himself put into place in legislation he co-sponsored with former Sen. Russ Feingold (D-Wis.). He has since voted against the DISCLOSE Act, which would have required companies and unions to reveal their political spending over $10,000.

Spokesmen for McCain and Mandel did not return requests for comment.

CORRECTION: An earlier version of this article misidentified Sen. Sherrod Brown as a Republican. Brown is a Democrat.

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