Get ready for some competition at the White House Correspondents' Dinner, Conan O'Brien. Proving once again that the president is one of the nation's best comedians, Obama led the annual Gridiron Dinner on Saturday night with jokes about Bob Woodward, Sen. Marco Rubio's water bottlegate, Secretary of State John Kerry and Nate Silver. Obama said he was "surprised" by the fight between Woodward and White House economic chief Gene Sperling since "who knew anybody named Gene could be so intimidating?" Obama ribbed Rubio's drink of water during his State of the Union response, joked that new Secretary of State John Kerry has been showing up for work in "disturbing" pantsuits, and the president called attention to New York Times columnist Nate Silver, calling him somebody "very special in my life."