After his return to Chile, he participated in the third Congress of his party, where they agreed to join the Third International and become the Communist Party of Chile. In 1919 he was deported to the south of the country for three months for speaking against the government. He was a candidate for the Chilean presidential election of 1920, where he lost to Arturo Alessandri. At the time of that election he was in re-incarcerated so he could not campaign and got a very small proportion of the vote. Nonetheless he was elected a deputy for Antofagasta again in 1921. After he moved to Santiago, he founded and edited "La Justicia" ("Justice") newspaper.