Arlen Specter (February 12, 1930 – October 14, 2012) was an American lawyer, author and politician who served as a United States Senator from Pennsylvania from 1981 to 2011. Specter was a Democrat from 1951 to 1965, then a Republican from 1965 until 2009, when he switched back to the Democratic Party. First elected in 1980, he was the longest-serving senator from Pennsylvania, having represented the state for 30 years.