"One thing I'm pretty confident of is that that decision would not be made by the president of the United States before the November election," he added.
McCain is scathingly critical of the political process in America today, blaming outside money for driving down the level of political discourse in 2012.
"I have not seen a campaign as poisonous as this is," he said. "I have not seen candidates call each other outright liars. It has to do with money. It has to do with these outside groups... We've reached the lowest level of discourse that I've seen in American politics."
McCain said the ratings for his 2008 convention were far higher than Romney's — crediting his controversial nominee for vice president, former Alaska Gov. Sarah Palin.
"She energized our party, and the nation," he said. "And the liberal left began a vendetta against her which is still the most disgraceful and despicable thing I've ever seen in American politics. No matter what she said they were going to try to destroy her with it."
But could it be that Palin's seeming lack of fluency in economic affairs tipped the election by frightening voters who at that precise moment were coming to terms with the terrifying dimensions of the Great Recession, creating a political market for expertise?
McCain bristled at the very proposition.
"I know of no campaign in history that hinged on who the vice presidential candidate was, so if your theory is correct it is a major breakthrough in the history of politics," he said.
Then he added, with what seemed like either sarcasm or resignation: "But it may be true."
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