Washington Post: “There may be no more important event on the calendar for Sanders than Iowa’s first-in-the-nation caucuses. He is counting on a political revolution to sweep him into the White House. But with Hillary Rodham Clinton regaining strength over the past month in the fight for the Democratic nomination, there’s a growing sense that Iowa could instead be the beginning of the end if Sanders doesn’t pull off back-to-back victories here and in New Hampshire.”

