Democracy And Partisanship
Since their expected utility is the product of the probability of winning times the proximity of policies to parties’ ideal point, parties trade off a lower probability of winning for a policy that is closer to their preference. The Wittman model has found wide application in the study of two-party systems, where one of its attractive features is that it can handle multidimensional spaces (more on this below). Another explanation for partisanship is that political parties, to be electorally successful, have to appeal to core constituents who provide the money and activists required to run effective electoral campaigns (Hibbs 1977; Schlesinger 1984; Kitschelt 1994; Aldrich 1993, 1995). Aldrich (1983) has formalized this idea in a Downsian model with party activists in which party leaders exchange policy influence to relatively extreme core constituents for unpaid work during campaigns.3 The logic is illustrated by the American primary systemwhere successful presidential candidates first have to win the support of the parties’ core constituents before they can contest the general election. In the general election they have an incentive to moderate their image to appeal to the median voter, but since they were chosen as candidates on different platforms, the perception among voters of real policy differences is accurate. Aldrich’s amended Downsian model raises a critical issue of commitment in politics—an issue that is also important for understanding partisanship. If the winning electoral platform in an election is the median voter preference, but candidates represent partisan constituencies, how can their commitment to the median voter be credible? Downs largely skirted this issue by assuming that party platforms had to be consistent over time, but it is now standard to assume that such commitments cannot be credible (Persson and Tabellini 1999, 2000). In modern political macroeconomics, for example, governments have a short-term incentive before elections to make the economy look better by using inflationary policies, even as such policies are unsustainable and have deleterious long-run effects (Alesina, Cohen, and Roubini 1992; Franzese 2002; Adolph 2005; Clark 2003).4 This creates room for partisan politics.5 “Citizen-candidates” models takes this idea to its logical conclusion by assuming that candidates cannot commit to anything other than their own preferred policies (Osborne and Slivinski 1996; Besley and Coate 1997).
With two candidates and costs of running, the equilibrium is away from the median voter because otherwise one citizen would not find it worthwhile to enter the race (why run if someone is already representing you?). With strategic voting this divergence can be quite large because voters may not want to switch from an existing candidate to a more moderate entrant in the fear that this may cause the least preferred candidate to win. Turning fromparty competition to government formation, new bargaining models also do not bear out the idea that the median legislator can dictate policy. If there is real bargaining taking place, Rubinstein bargaining theory essentially implies that parties will split their policy differences. The threat to break off negotiations and initiate bargaining with another party cannot easily be used by the median party to get its way. The reason is that if there are any costs of switching (which may simply be the cost of a delay), the new bargaining partner has no incentive to offer a bargain that is better than the original minus the cost of switching.6 As long as parties have different policy preferences, as in the citizen-candidate model, governments will therefore be away from the median. But while there are compelling reasons why partisanship matters, a critical issue that has largely been skirted is why some countries are dominated by centerleft governments and others by center-right governments. In the absence of such dominance we may get partisan political business cycles, as argued by Alesina and others (Alesina, Cohen, and Roubini 1992), but partisanship could no longer explain persistent cross-national differences in policies and outcomes.Nor could partisanship serve as a credible commitment mechanism as it does in the Lange–Garrett model (since partisanship would change in the future).
In fact, government partisanship does vary significantly across democracies (see Powell 2002; Iversen and Soskice 2002), and much of the evidence for the importance of partisanship is cross-national. Rather surprisingly, most of the literature also fails to distinguish between the preferences of parties and the preferences of voters. Observed policy differences between left and right governments could be due to either. There are methodological fixes to this problem—such as comparing the ideological composition of the government to that of the legislature, or focusing on “natural experiments” where the outcome approximates a random assignment of the partisan “treatment” (say, in very close elections)—but we also need a theory of voter preferences. Since voters have an incentive to be “rationally ignorant,” as argued by Downs many years ago, it is not really satisfactory to assume that parties simply reflect the interests of citizens. Partisan models must also explain how interests are defined and become common knowledge—a major agenda for future research..
