Louisiana congressman Charles Boustany has won a fifth term by handily defeating his Republican colleague, Jeff Landry, in a runoff election.
Boustany was winning 60 percent of the vote with 85 percent of precincts reporting late Saturday.
The two were forced into the same district when Louisiana lost a seat because of anemic population growth in the latest federal census.
Boustany will represent the 3rd District covering southwest Louisiana and Acadiana next year. Republicans will control five of Louisiana's six congressional seats.
The race had been attack-heavy, since both men ran as conservative Republicans and had little philosophical ground in which to distinguish themselves.
The district design favored Boustany, a traditional Republican allied with House Speaker John Boehner. Landry, a freshman congressman, was the tea party favorite.