The Republicans regained the majority of the Senate in the 114th Congress, which started in January 2015; the Republicans had not controlled the Senate since January 2007. They needed a net gain of at least six seats to obtain a majority and were projected by polls to do so. On election night, they held all of their seats and gained nine Democratic-held seats. Republicans defeated five Democratic incumbents: Mark Begich of Alaska lost to Dan Sullivan, Mark Pryor of Arkansas lost to Tom Cotton, Mark Udall of Colorado lost to Cory Gardner, Mary Landrieu of Louisiana lost to Bill Cassidy, and Kay Hagan of North Carolina lost to Thom Tillis. Republicans also picked up another four open seats in Iowa, Montana, South Dakota, and West Virginia. Democrats did not pick up any Republican-held seats, but they did hold an open seat in Michigan.