A well-established body of literature links voter turnout to political campaigns. In this view, intensive campaigns increase the perceived salience of a decision, fostering information-seeking and, ultimately, turnout. The existing literature has also advanced our understanding of how direct democratic institutions influence turnout in elections. Yet we still know little about whether and to what extent campaign efforts influence voter turnout in direct democratic votes, and we know even less about who is mobilized. We claim that campaign intensity has differentiated effects across voters, depending on voters' participation profile. To test this claim we use a rich dataset of official turnout data covering more than 40 direct democratic votes in Switzerland. The results support our claim. While intensive political campaigns overall foster citizens to turn out to vote, they do so especially for “selective” (or “intermittent”) voters, who need to decide anew at each ballot whether to turn out or not. Interestingly, we also find that frequent abstainers are not immune from campaign effects, and get almost as strongly mobilized as selective voters in highly intensive campaigns.