In 1960, he became a founding member and Secretary General of the Christian Democratic Party (PDC), which searched for a middle ground between the extreme right and the extreme left. Even as part of the United Democratic Party (PUD), the PDC failed to gain a seat in that year's National Congress elections. After boycotting the 1962 presidential elections, Duarte became Mayor of San Salvador in March 1964. He initiated the Adult Evening Schools helping a lot of adult workers to become technicians and also get high school diplomas. He supported emerging sectors of the economy and some redistribution of wealth. Duarte easily won the next two elections for mayor in March 1966 and March 1968.