John Cornyn is an American politician serving as the senior United States Senator from Texas. He has been in office since 2002 and is a member of the Republican Party. Before his tenure in the Senate, Cornyn served as the Attorney General of Texas from 1999 to 2002 and was a state judge. As a senator, Cornyn has focused on various issues, including national security, immigration reform, and economic growth. He is known for his leadership roles within the Senate, including serving as the Senate Minority Whip. Cornyn has been involved in numerous legislative efforts throughout his career.