WASHINGTON – Two days from the White House, President-elect Barack Obama joined a vast throng Sunday at a roaring, rollicking pre-inauguration celebration staged before marble monuments to past heroes. "Anything is possible in America," declared the man who will confront economic crisis and two wars when he takes office. "Despite the enormity of the task that lies ahead — I stand here today as hopeful as ever that the United States of America will endure — that the dream of our founders will live on in our time," the president-elect said at the conclusion of a musical extravaganza that featured...