Mary Loretta Landrieu is an American politician and businesswoman who served as a United States Senator from Louisiana from 1997 to 2015. A member of the Democratic Party, she previously served as the Louisiana State Treasurer from 1988 to 1996. Throughout her career, she was known as a moderate Democrat, often focusing on issues related to energy, coastal restoration, and disaster recovery. After leaving the Senate, she became a senior policy advisor at a law firm and has been involved in various business ventures.