Following the 1955 overthrow of populist President Juan Perón, Guzmán was named Director of the Provincial Social Security Fund, and he became head of the Jujuy UCR. The schism in the UCR following its 1956 convention led Guzmán to join the more progressive, UCRI, however, which defeated the rival UCRP in the February 1958 general election. Guzmán ran for and won the governor's post in Jujuy by a wide margin, and he promptly adopted the developmentalist policies advanced by the UCRI standard-bearer, President-elect Arturo Frondizi.