Amending the outdated constitution had been attempted by earlier governors. In 1963 Governor Scranton appointed Lt. Gov. Ray Shafer to be chair of a bipartisan committee to promote constitutional reforms. The Convention consisted of one hundred citizens who met in 1967-68, and whose proposals were brought to a voter referendum on April 23, 1968. The campaign to approve the amendments required voting "yes" nine times. To bring this project to a successful conclusion required considerable political finesse and may represent Shafer's longest-lasting contribution to Pennsylvania history.
Analysts agree that Shafer's popularity as governor waned as his term wore on. There were difficulties in funding the numerous state projects, particularly with the high inflation that characterized these years. Faced with an budget deficit of $250 million, Shafer advocated the implementation of a personal state income tax, a move that proved unpopular with Pennsylvanians. Until the 1968 constitutional revision, no Pennsylvania governor was permitted to succeed himself in office, and Shafer was ineligible for a second term. In the 1970 gubernatorial race, the Republican candidate, Shafer's own Lt. Governor Raymond Broderick, ran as a direct opponent of the income tax, but was defeated. In the 1970 elections, the Democrats regained firm control of the Pennsylvania legislature for the first time since 1936 and elected Milton Shapp who served two terms as governor (1971-1979).