Even today, seniority matters in the U.S. Senate, with office suite and committee assignments favoring longer-serving members over their more junior colleagues. But since no two senators can ever have precisely the same seniority, the Senate maintains a formula for breaking ties between freshmen senators who are sworn in on the same day. Preference is given, in order, to former senators, U.S. House members, former cabinet secretaries, and governors, with state population serving as the ultimate tie-breaker.
At least 11, and perhaps more than 15, new senators will officially take office on January 3, 2013, and after the jump check out how they would rank by seniority upon their arrival. (Only open seat candidates and challengers with realistic prospects for victory are included).