The senate curse:
Harding and Kennedy are the only two senators who have won the White House. That's not because other senators haven't tried. Some big-name senators in U.S. history failed to parlay their Senate careers to the White House, including Henry Clay, Daniel Webster and Michigan's Lewis Cass, defeated in 1848 by Taylor.
Today's Senate is heavy with ex-presidential candidates: Joe Lieberman, Bob Graham, Orrin Hatch, Richard Lugar, Tom Harkin, John McCain and Ted Kennedy.
But 12 senators have become vice president, three of them eventually becoming president (Truman, Nixon and Lyndon Johnson).
