 Considered one of the most prominent Democrats in New Jersey , he became a candidate for the United States Senate in the 2013 special election to succeed Frank Lautenberg , who died in office . He won the Senate Democratic primary on August 13 , 2013 , and then won the general election against Steve Lonegan on October 16 , 2013 , becoming the first black U.S. Senator from New Jersey . Booker subsequently won the next regular election for the Senate seat against Jeff Bell in 2014 . 
