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In this photo taken Dec. 13, 2007, Democratic presidential hopeful Sen. Hillary Clinton, D-N.Y. speaks at right as Democratic presidential hopeful Sen. Christopher Dodd, D-Conn. and Democratic presidential hopeful former Sen. John Edwards, D-N.C. listen during the Des Moines Register Democratic Presidential Debate in Johnston, Iowa. Hillary Clinton has appeared in more than 30 primary debates during her two presidential campaigns, a deep history she can draw upon as she faces Donald Trump on Monday, Sept. 26, 2016. Clinton has been through the debate gauntlet in two New York Senate campaigns as well as in presidential primary match-ups against then-Sen. Barack Obama in 2008, Vermont Sen. Bernie Sanders this year and other challengers. (AP Photo/Charlie Neibergall)

John Edwards

John Edwards