Cappellini served as Mayor of Villa Ojo de Agua, a position later held by her husband. She then served as a provincial deputy.[2] In the provincial legislature she led the Bases Populares block. In 2007 Cappellini was elected to the Argentine Senate for the Civic Front of Santiago, a front formed in 2005 by Radicals and Peronists. She and her fellow Civic Front senator Emilio Rached form their own block but support the Kirchners' Front for Victory.