Receiving about 50 percent of the vote in Louisiana on Saturday, Republican attorney Joseph Cao has become the first Vietnamese American in the US House of Representatives.
Forty-one-year-old Cao Quang Anh, as his full Vietnamese name reads, defeated Democrat William Jefferson, who received 47 percent of the vote, Reuters reported.
Two other candidates each received small percentages.
Cao won in the 2nd congressional district, including most of New Orleans, which was ravaged by Hurricane Katrina in 2005. Saturday's election had been put off because of Hurricane Gustav, which threatened the city in September and delayed the Democratic primary.
Jefferson, who has been in Congress since 1991, was accused last year of soliciting millions of dollars in bribes from a dozen companies while using his office to broker business deals in Africa. In a search of his home in 2005, FBI agents said they found US$90,000 in bribe money in a freezer.
Cao, a political newcomer, started his bid for Congress following his successful campaign to help New Orleaners rebuild their city after Hurricane Katrina.
He came to the US in 1975, having acquired law, physics and philosophy degrees.
As an emigration lawyer and now Louisiana's representative in the lower house, Cao said he would talk more about immigration matters to the Congress.
"The people of the 2nd District have spoken. We want new direction. We want action. We want accountability," BBC cited Cao as telling supporters.