The 1991 United States Senate Special election in Pennsylvania was held on November 5, 1991, after incumbent Republican Senator John Heinz died in a plane crash on April 4 of that year. Democrat Harris Wofford was appointed to the seat by Governor Bob Casey, and won the general election over Republican Dick Thornburgh, a former Governor and U.S. Attorney General. Wofford became Pennsylvania's first Democratic Senator since Joseph S. Clark Jr. left office in 1969. Major-party candidates for this election were chosen by party committees, as the vacancy had happened too late for a primary to be held.