The song, set to the tune of "Puff the Magic Dragon, " was first played on conservative political commentator Rush Limbaugh's radio show in 2007.

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Radio talk show host Rush Limbaugh called her "an affirmative action case extraordinaire, " although affirmative action doesn't help you graduate summa cum laude from an Ivy League university.

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He said he genuinely believes that some congressional Republicans are open to compromise, but fear the party's conservative base and what talk show host Rush Limbaugh might say about them.

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Still, Republicans are starting to get their sea legs after spending months of serious soul-searching and having to watch the likes of Palin, Steele and conservative radio talk-show host Rush Limbaugh dominate the news cycle -- for all the wrong reasons.

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Conservative talk show hosts, including Rush Limbaugh and Laura Ingraham, have blasted McCain in recent weeks, calling him too liberal and saying his nomination would split the party.

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It later emerged that conservative radio host Rush Limbaugh made the same joke in his show earlier on Thursday, something Mr Johnson acknowledged in his Twitter feed after the debate.

BBC: Rick Perry (left) and Mitt Romney