**ADVANCE FOR SEPT. 28**U.S. Congressman Ben Cardin, D-Md., left, a U.S Senate candidate, rallies with Sen. Barack Obama, D-Ill., second from left, Sen. Barbara Mikulski, D-Md., third from left, and his former primary campaign opponent Kweisi Mfume, right, Wednesday Sept. 27, 2006 at the University of Maryland at College Park in College Park, Md. (AP Photo/ Steve Ruark)