When do political protests influence citizens’ behaviour? Do environmental protests have electoral consequences? In this paper, I build on social-psychological work to argue that a key characteristic of effective protests is their capability to repeatedly expose voters to their message. I test this argument by studying the effect of FFF protests on voting for Green Parties. Using a novel dataset on FFF protests in Germany, and a difference-in-differences design, I find that exposure to environmental protests increases the vote share of the Greens, and that repeated exposure to protests increases this effect. Additional analyses suggest that repeated exposure persuades voters of FFF's policy positions, and that these effects travel to other countries, but not to other environmental-friendly behaviours. Overall, these results are important to understand when and how protests are influential, as well as to understand the political consequences of environmental protests.