Social Democracy and Party Competition: Mapping the Electoral Payoffs of Strategic Interaction
This chapter focuses on the electoral performance of social democratic parties in different institutional and competitive contexts. We explore three avenues to shed light on the relationship between social democratic parties' strategic interaction with competitors and their respective electoral payoffs. We start from premises of spatial theories of party competition but hypothesize only behavioral relations between party choices and electoral outcomes, not strategic equilibrium configurations. We ask three questions: first, holding all other parties' positions constant, do party positions closer to the center of a policy dimension – where empirically most voters are located – pay off in electoral terms and does this effect vary across relevant dimension of party competition? Second, does distance of parties from competitors improve their electoral fortunes? Taking spatial considerations of the first two questions together, are parties electorally better off if they place themselves closer to the center of policy spaces, while simultaneously facing only distant competitors? Third, what are the electoral consequences of two focal parties – a moderate left (social democratic) and a moderate right (conservative or Christian Democratic or People's) party – simultaneously choosing positions in a multiparty field? These consequences may be different for the individual parties and for their ideological “field.” The performance of individual parties turns out to be much in line with spatial theory: When Social Democrats move to the center, they are likely to win voters from the center-right, but lose votes to green-left and radical-left parties within the left field. Social Democrats often perform stronger when they move left than to the center. But there is a crucial difference between their choices when it comes to considering the electoral performance of the entire set of left-field parties. By moving to the center, and shedding votes to their leftist competitors, Social Democrats sometimes effectively increase the size of the leftist field and thereby also boost their own bargaining power over coalition governments, as they are usually the most moderate party in the left field and most capable of crafting coalitions with parties of the center-right, particularly if Social Democrats control the median voter.
