In 2010, Dayton defeated Republican Tom Emmer to become governor of Minnesota despite national success for the Republican Party, including in the Minnesota legislature. He won a second term in 2014 over Republican opponent Jeff Johnson and opted not to run for a third term in 2018, leaving office in January 2019. His major legislative initiatives as governor include the legalization of same-sex marriage and the construction of U.S. Bank Stadium for the Minnesota Vikings of the National Football League (NFL).