The 2008 United States Senate election in Louisiana was held on November 4, 2008. This was the first time since the 1970s that Louisiana used primaries for federal races. Incumbent Democratic U.S. Senator Mary Landrieu won reelection to a third term. As of 2016, this is the last Senate election in Louisiana that was won by a Democrat.
Landrieu's increased vulnerability was supposed to be the result of a significant drop in the state's African-American population after Hurricane Katrina, especially in Landrieu's home city of New Orleans. Louisiana also elected a Republican senator in 2004 and President Bush carried the state twice, in 2004 with 58 percent of the vote. Also, Republican Congressman Bobby Jindal won the 2007 gubernatorial election with 54 percent of the vote.
CQ Politics rated this race as 'Leans Democrat'.The Cook Political Report considered it 'Lean Democrat'.The Rothenberg Political Report considered it a 'Narrow Advantage for Incumbent Party'. Landrieu was considered the most vulnerable Democratic senator up for re-election in 2008.