Jimmy Hoffa to the U.S. Senate in the 1964 election. Hoffa spent the next three years unsuccessfully appealing his 1964 convictions. Appeals filed by his chief counsel, St. Louis defense attorney Morris Shenker, reached the U.S. Supreme Court. He began serving his sentences in March 1967 at the Lewisburg Federal Penitentiary in Pennsylvania. Just before he entered prison, Hoffa appointed Frank Fitzsimmons as acting Teamsters president. Fitzsimmons was a Hoffa loyalist, fellow Detroit resident, and a longtime member of Teamsters Local 299, who owed his own high position in large part to Hoffa's influence. Despite this, Fitzsimmons soon distanced himself from Hoffa's
Jimmy Hoffa bid in 1972; in prior elections, the union had supported Democratic nominees but had also endorsed Nixon in 1960. Suspicion was soon raised of a deal for Hoffa's release connected with the IBT's support of Nixon. It was alleged that a large sum of money, estimated to be as high as $1 million, was paid secretly to Nixon. Evidence was also alleged of a secret bribe paid in 1960. While glad to regain his freedom, Hoffa was very disappointed with the condition imposed on his release by President Nixon, which prevented Hoffa from engaging in union activities until March 1980.