Ideological Congruence, Voter Polarisation and Electoral Participation

Why are some parties more ideologically congruent with the median voter, while others are more closely aligned with their core constituents? In this paper, I shed light on parties’ electoral strategies by focusing on the distribution of voter preferences and electoral participation. Building on assumptions which underlie the Downsian approach to electoral competition, I suggest that parties often face strong incentives to represent their core constituents instead of converging on the median voter. Core constituents are defined on the basis of socioeconomic cleavages that have traditionally dominated party competition. I argue that parties’ incentives to represent the median voter increase as voter preferences approximate a normal distribution. In contrast, as voters become polarised, parties will be more likely to target their core constituents. The distribution of voter preferences is thus a key determinant of the electoral payoffs associated with each mode of representation. An additional factor examined in this paper is electoral participation. When citizens abstain from voting because they feel no longer adequately represented, parties have an incentive to adjust their electoral strategy. I argue that parties become more ideologically congruent with their core constituents when turnout among that group falls. By combining data from the Comparative Manifesto Project and various national election studies, I test these arguments through a comparative analysis of party programmes in 6 European countries and 18 parties over the period of 1973 to 2013. This study offers a novel explanation for why parties favour one electoral strategy over another.