Ten years after : Is the party-centered theory of campaign professionalization still valid?

This study tests the explanatory strength of the party-centered theory of electoral campaign professionalism. The theory was previously subject to testing in various types of elections during the first decade of the new millennium, covering Germany, Austria, Sweden, and Finland. Nevertheless, empirical research in this field has been on hold for almost a decade, obstructing the development of the theory during a time when politics and political campaigns have taken new paths. In this article, the theory is revisited, presenting results from a unique time series study covering 48 party campaigns between 2009 and 2019 in three consecutive European parliamentary elections in two multiparty democracies, Sweden and Finland. Our results provide weak support for the party-centered theory of campaign professionalism in the form it was originally operationalized. Only a centralized party organization and a large support base with a catch-all strategy were found to be statistically significant predictors of campaign professionalism.Peer reviewe