Louisiana Senate race headed to runoff election in December

WASHINGTON (AP) -- Republicans have picked up four of the six seats they need for a Senate majority, while Louisiana's hard-fought Senate race is headed to a runoff.

Republican Steve Daines won a Democratic Senate seat in Montana. Daines is moving to the Senate after just one term in the House. He won election over state lawmaker Amanda Curtis, who became the Democratic nominee after Sen. John Walsh dropped out of the race amid a plagiarism scandal.

Daines' win follows Republican pickups in Arkansas, South Dakota and West Virginia.

In Louisiana, neither Democratic Sen. Mary Landrieu nor Republican challenger Bill Cassidy received more than 50 percent of the vote, necessitating a runoff under Louisiana law.

Republican Mike Enzi of Wyoming and Democrat Al Franken of Minnesota also won re-election.

More on AOL.com:
GOP mounting powerful bid for Senate control
Senate News Guide: Rundown on race for control
The moment NBC anchor Tom Brokaw's cell phone rings during election night newscast