Serpa was re-elected for the periods of 1978 and 1982 under a movement founded by him, the Authentic Liberal Leftist Front (Frente de Izquierda Liberal Auténtico, FILA) aligned with the official Liberal party.
sˈɜːpə wʌz ɹˌiːᵻlˈɛktᵻd fɚðə pˈiəɹɪədz ʌv nˈaɪntiːnhˈʌndɹɪd sˈɛvənti ˈeɪt ænd nˈaɪntiːnhˈʌndɹɪd ˈeɪɾi tˈuː ˌʌndɚɹ ɐ mˈuːvmənt fˈaʊndᵻd baɪ hˌɪm, ðɪ ɔːθˈɛntɪk lˈɪbɚɹəl lˈɛftɪst fɹˈʌnt fɹˈɛnt də ˈɪzkwɪɹdə lˈɪbɚɹəl ɔːtˈeɪntɪkˌoʊ, fˈiːlə ɐlˈaɪnd wɪððɪ əfˈɪʃəl lˈɪbɚɹəl pˈɑːɹɾi.