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Arizona Sen. John McCainJohn Sidney McCainMeghan McCain on Pelosi, McCarthy fight: 'I think they're all bad' Democrats seek to counter GOP attacks on gas prices Biden nominates Jeff Flake as ambassador to Turkey MORE (R) defended Mitt Romney on Sunday, amid concerns the GOP frontrunner is failing to rally the party’s conservative base and may fall short of the delegates needed to win the nomination outright.

McCain, on NBC’s “Meet the Press,” said Romney was aware that he needed to change his approach in order to close out the GOP presidential race.


“Obviously Mitt Romney will tell you first of all he's got to do a better job. He's working on doing a better job,” said McCain. “He's got to focus more on the economy."

McCain added that Romney, who lost two key Southern primaries on Tuesday, was “improving dramatically as a candidate.”

The 2008 GOP presidential nominee, said Romney, whom McCain is backing for the presidency, had been hurt by the revamped GOP nominating process where many early contests awarded their delegates proportionally, delaying Romney’s ability to deliver a knock-out blow to his rivals.

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“In any campaign before him we had winner take all, in winner take all you would assume those numbers would be significantly different.,” McCain said of Romney’s delegate totals.

Speculation has grown that neither Romney nor his rivals former Pennsylvania Sen. Rick Santorum, former House Speaker Newt Gingrich (Ga.) or Texas Rep. Ron Paul will secure the delegates needed before the convention.

But McCain dismissed the chances Republican voters would see a brokered convention. “I just don't think it’s going to happen,” he said.

McCain also pointed to the role of super-PACs, which  can spend unlimited expenditures for or against political candidates, as long as candidates are not involved in their process.

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“Super-PACs have played a key role, unfortunately negative in my view because they've driven up the unfavorables of all candidates and frankly made it more difficult to win an election in November," McCain said.

“If you have a Las Vegas casino mogul, by the way who gets part of his money from Macau, pouring $20 million into one campaign and most of those are negative ads, obviously that drives up people's unfavorables,” he added in reference to businessman Sheldon Adelson who has donated millions to Gingrich’s campaign and super-PAC.

"This is the nastiest fight I've ever seen," the Arizona senator said of the GOP race.

“It’s gone on too long, and its gotten way, way too personal,” he added.

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