Liberal leader and Prime Minister Lester Pearson announced on December 14, 1967, that he would be retiring in April 1968. Pearson had been Liberal leader since 1958 and Prime Minister since 1963. He was still much liked by the party and by the Canadian people in general, but he had failed in two attempts to win a majority government. The Liberals were also trailing in the polls behind the Progressive Conservatives, whose popular new leader Robert Stanfield had been selected in September 1967.