WASHINGTON (Reuters) - Democratic Sen. John Kerry, whose baffling explanation of votes on Iraq war funding hurt his 2004 White House bid, said on Tuesday he would back President Bush's new $81.9 billion request for Iraq and Afghanistan. "I think we're in a very different situation," Kerry told reporters. "I'm going to vote for this ... I think this money is important to our being successful and to the completion of the process." The Massachusetts senator, who failed in his bid to unseat Bush last November in an election focused on national security, defended his decision to not back the...