2008 presidential hopeful Hillary Clinton said Monday that she's horrified over allegations that U.S. Marines executed innocent Iraqis in the town of Haditha last November after their convoy was hit by a roadside bomb - and she's vowing to expose any cover-up by Marine brass. "This is the kind of horrific allegation that has to be investigated, and we're going to start in the Senate doing just that," she told the New York Daily News, after marching in Chappaqua's Memorial Day parade. The comments by Clinton, who sits on the Senate Armed Services Committee, seemed to contradict remarks by committee...