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Sen. John McCain and Sen. Barack Obama head to Mississippi tonight for the first presidential debate of the general election.
For a walk down memory lane (presidential debate edition), check out this video produced by ABCNews.com producer Lindsey Ellerson on memorable debate moments in the election cycles of yore.
And while there were questions on top of questions as to whether or not the debate would go on as scheduled, pundits volleying back and forth over whether it should or shouldn't, ABC News' Polling Director Gary Langer blogs on whether the candidates' debate performances even matter.
Gary writes, "Directly and measurably, generally not. But indirectly or more subtly, likely so. And there are plenty of reasons to think that this year's campaign could be especially sensitive to the candidates' debate performances."
"Debates have been held in nine presidential contests since 1960. We find just one after which the lead changed hands by a clearly significant margin: In 1980, when Ronald Reagan uttered his "are you better off" line. He gained 7 points in a post-debate poll."
If you don't have time for the full video, click here for a slideshow of the best debate moments from 1960 through 2004 to get up to speed before tonight!