He resumed his activities in the UCR, and was elected to successive party committee posts. Gómez joined former Córdoba Province Governor Amadeo Sabattini's Intransigence and Renewal Front (MIR) upon its establishment in 1945. The MIR was a liberal wing of the UCR formed in opposition to the party's alliance with conservatives in the Democratic Union coalition. The MIR instead endorsed the populist Labor Party candidate, Juan Perón, who would go on to win the 1946 elections. Gómez, like most in the MIR, later became disillusioned with Perón and returned to the UCR fold. He joined Arturo Frondizi's UCRI, however, and became his nominee for the Vice Presidency when the latter split from the UCR during the November 1956 convention in Tucumán due to opposition of UCR leader Ricardo Balbín's hard-line stance against Peronists (who had been banned following the 1955 coup against President Perón).