Explaining Voter Responses to Mainstream Parties’ Moderation Strategies

To what extent does moderation in ideological positioning by mainstream parties affect their short and long-term electoral fortunes? Do electorates treat the major parties of the center-left and center-right differently when these types of parties move to the middle? Previous research reports that social democratic parties receive an influx of centrist voters post-moderation, but that these new centrist voters are less attached to the party and leave in later elections, as do left-leaning social democrats frustrated by moderation strategies. These losses exceed expectations based on the costs of governing, partisan dealignment, or trends towards lower turnout. The present paper applies this idea to the broader spectrum of mainstream parties. If supporters of center-right parties respond in a similar fashion to ideological moderation, a common theoretical framework connecting mainstream parties and their voters helps us understand how the ideological convergence of major political parties facilitates minor party success and increases the salience of competition on non-economic issues.