New communication technologies can be a weapon to increase the political power of entrenched elites—either through coercion or mobilization—but can also enhance new challenger parties. In this paper we explore the political consequences of telephone network expansion in electoral autocracies by focusing on Catalonia between 1901–1923. We analyze the political consequences of a new public telephone network through a DiD identification strategy, and exogeneize telephone extensions through distances to the existing private networks to verify the robustness of our findings. Our main results show that the extension of telephone networks benefited new challenger parties and reduced support rates for status quo elite parties. The empirical analyses reflect a double dynamic of (i) elite replacement of status quo elites by new economic elites, and (ii) left-wing voters’ mobilization associated with telephone expansions.