In July 1961, two years after the 1959 Revolution, the Integrated Revolutionary Organizations (IRO) was formed, merging Fidel Castro's 26th of July Movement with Blas Roca's Popular Socialist Party and Faure Chomón's Revolutionary Directory 13 March. On 26 March 1962, the IRO became the United Party of the Cuban Socialist Revolution (PURSC), which, in turn, became the Communist Party on 3 October 1965, with Castro as First Secretary. In 1976 a national referendum ratified a new constitution, with 97.7% in favour. The constitution secured the Communist Party's central role in governing Cuba, but kept party affiliation out of the election process. Other smaller parties exist but have little influence and are not permitted to campaign against the program of the Communist Party.