In June 1966, Joaquín Balaguer, leader of the Reformist Party (which later became the Social Christian Reformist Party (PRSC)), was elected and then re-elected to office in May 1970 and May 1974, both times after the major opposition parties withdrew late in the campaign because of the high degree of violence by pro-government groups. On November 28, 1966 a constitution was created, signed, and put into effect. The constitution stated that the president was elected to a four-year term. If there was a close election there would be a second round of voting to decide the winner. The voting age was eighteen, but married people under eighteen could also vote.