Thomas Carper. I've never heard of him either.
He replaced Roth in 2001.
He was the lone Congressman from Delaware before "switiching" places with Mike Castle as Governor in '92. He then went on to defeat Bill Roth in 2000, a defeat which lead to Roth's premature death, IMHO. He ran a very nasty campaign against a very good man.
I have known both Biden and Carper for over 20 years. I have far more respect for Joe Biden than Tom Carper and that is saying alot considering I have about no respect for Biden.