 Later, he became involved with the political group "Estadistas Unidos", founded by Luis Ferre.Romero was one of the founding members of the New Progressive Party in 1967.The following year he was elected Mayor of San Juan, Puerto Rico, succeeding the legendary "doña Fela" (Felisa Rincón de Gautier) and becoming the first popularly elected mayor of San Juan, since previous mayors were elected by the San Juan City Council, not directly by the electorate.