William Jefferson was elected to the U.S. House in 1990 with 52 percent of the vote, defeating Democrat Marc Morial for a seat vacated by retiring Democrat Rep. Lindy Boggs. Jefferson received only token opposition in 1992 and 1994. In 1992, Jefferson received 73 percent of the vote in a three-man race. In 1994, he received 75 percent against four others. He was uncontested in 1996, 1998, 2000 and 2002.
Jefferson served in the Louisiana Senate, from 1980 to 1990. He ran unsuccessfully for mayor of New Orleans in 1982 and 1986. In 1995 and 1999, Jefferson ran unsuccessfully for governor.