Replication material for: “When do subnational jurisdictional mergers impact voting?”

Despite numerous territorial reforms of municipalities and regions across Europe, the impact of jurisdictional mergers on voting, i.e., citizens' party vote choice and parties' vote shares, has received scant attention in the literature. In this article, we explore the conditions under which jurisdictional reforms impact voting. We argue that citizens base their vote choice on their merger position when they find the merger issue important and that they are more likely to do so in second-order elections, i.e., in elections that are perceived to be less important. Furthermore, merger-based voting depends on the politicization of the merger process, which is affected by the reform process (top-down versus bottom-up) and whether merger outcomes are in line with the affected communities’ preferences or not. Leveraging the 2020 local government reform in Norway, and drawing on both survey and aggregate data, we find that citizens who oppose a merger and find the merger issue important are more likely to vote for an anti-merger party, especially in second-order county elections. At the aggregate level, top-down county mergers that were implemented against the will of the involved constituencies increase the vote shares for anti-merger parties in county (second-order) elections. These results are important because they reveal that subnational jurisdictional reform is clearly linked to vote choice in subnational elections. Thereby, our study adds to an increasing body of research that reveals that citizens care about jurisdictional design at subnational and supranational levels.