Keep in mind that Senator Dayton's daddy is a confounder of the Dayton-Hudson-Target retail empire and couldn't find a job which the kid could handle. Thus, he became a professional at running for office. He developed high name recognition with the family bankroll and losing elections. As was bound to happen, sooner or later, he got lucky with (a)the opposition putting up a poor candidate or (b)a convenient scandal and gradually rose through the ranks.
In 2000, the incumbent Rod Grams was a great senator, but had a delinquent son who couldn't manage his zipper and got caught in a motel room with an under-aged bimbo just before election time. As a result, the voters awarded Dayton the senate seat.
He's got to be the dumbest male in the U.S. Senate. Thanks to Patty Murray and Barbara Boxer, he's only the third dumbest person.