Place-Based Campaigning: The Political Impact of Real Grassroots Mobilization Daniel Bischof Aarhus University & University of Zurich Thomas Kurer University of Konstanz & University of Zurich September 3, 2021 Abstract Generations of research have incrementally identified the circumstances under which electoral campaigns matter. Direct, interpersonal contact within local networks is commonly seen as con- ducive to campaign impact but empirical evidence is scarce due to demanding data require- ments. We advance the literature by studying the Movimento Cinque Stelle, an important chal- lenger party in Italy, which followed the unusual practice of coordinating all political activities on a public online platform. We webscraped the entire event history of the Movement’s more than 1,000 local branches with over 200,000 geocoded political activities to study the eect and mechanisms of their campaign against the 2016 constitutional referendum – a watershed moment in Italian politics. Relying on regression, matching, and instrumental variable models, we demonstrate substantial campaign eects. Our results indicate that social networks amplify the eectiveness of a campaign while highlighting both the continued relevance and the partic- ular potency of place-based political mobilization. word count abstract = 149; full manuscript (excluding abstract)= 10,728. Correspondence:
[email protected]. We thank Tarik Abou-Chadi, Reto Bürgisser, Francesco Colombo, Elias Dinas, Sarah Engler, Florian Foos, Hanno Hilbig, Swen Hutter, Herbert Kitschelt, Hanspeter Kriesi, Arndt Leininger, Giorgio Malet, Tabea Palmtag, Nils Redeker, Tobias Rommel, Roman Senninger, Zeynep Somer-Topcu, Resul Umit, Kateřina Vráblíková, Vicente Valentim, Valerio Vignoli, Markus Wagner, and conference participants at EPSA 2019, APSA 2019, SVPW 2020, the Workshop on “Under pressure: Electoral and non-electoral participation in polarizing times”, and during an invited talk at the University of Gothenburg for helpful comments.