Premise: Joe Biden . A member of the Democratic Party , he represented Delaware as a United States Senator from 1973 until becoming Vice President in 2009 . He was re-elected to the Senate six times , and was the fourth most senior senator at the time of his resignation to assume the Vice Presidency in 2009 . The United States Senate elections , 1972 was an election for the United States Senate coinciding with the landslide re-election of Republican President Richard Nixon .
Hypothesis: Joe Biden was a US senator.
Label: ENTAILMENT