Manchin is a conservative Democrat who has continued to win elections in West Virginia even though the state now leans heavily Republican. He won the 2004 gubernatorial election by a large margin and was reelected by an even larger margin in 2008; in both years, Republican presidential candidates won West Virginia. Manchin won the special election in 2010 to fill the Senate seat vacated by Robert Byrd when he died in office. Manchin was elected to a full term in 2012 with 60% of the vote and reelected in 2018 by a much narrower margin. He became the state's senior U. S. Senator when Jay Rockefeller retired in 2015.