Similarly, President George W. Bush and his 2004 Democratic challenger, Sen. John Kerry of Massachusetts, knew each other from work in Washington. Same with President Bill Clinton and then-Kansas Sen. Bob Dole, the Republican nominee in 1996.
Sara Taylor Fagen, who served as a political adviser to Bush, said Obama and Romney's lack of a personal relationship would likely be a mixed blessing on the debate stage.
"On the one hand, you've depersonalized it. You can say, 'I don't really know you, I'm totally comfortable saying whatever I have to," Fagen said. "On the other hand, familiarity is a really helpful thing. Even though you may be fierce opponents, it also gives you a comfort level."
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