This paper analyzes the effects on voting behavior of information disseminated over the Internet. We address endogeneity in Internet availability by exploiting regional and technological peculiarities of the preexisting voice telephony network that hindered the roll-out of fixed-line infrastructure for high-speed Internet. We find negative effects of Internet availability on voter turnout, which we relate to a crowding-out of TV consumption and increased entertainment consumption. We find no evidence that the Internet systematically benefits specific parties, suggesting ideological self-segregation in online information consumption. Robustness tests, including placebo estimations from the pre-Internet period, support a causal interpretation of our results. (JEL D12, D72, L82, L86)