Policy Inertia, Election Uncertainty, and Incumbency Disadvantage of Political Parties

We document that postwar U.S. elections show a strong pattern of “incumbency disadvantage”: if a party has held the presidency of the country or the governorship of a state for some time, that party tends to lose popularity in the subsequent election. We show that this fact can be explained by a combination of policy inertia and unpredictability in election outcomes. A quantitative analysis shows that the observed magnitude of incumbency disadvantage can arise in several different models of policy inertia. Normative and positive implications of policy inertia leading to incumbency disadvantage are explored.

Incumbency, Parties, and Legislatures: Theory and Evidence from India

Incumbent legislators in some developing countries are often thought to face an electoral disadvantage relative to challengers. This article traces this effect to high levels of centralization within the political parties and governments of these countries. In political systems dominated by party leaders, legislators face substantial formal and informal constraints on their ability to influence policy, stake positions, and control patronage, which in turn reduce their ability to build up personal votes. This theory is tested on a dataset of Indian national elections since 1977, using a regression discontinuity design to measure the effects of incumbency. Candidates less affected by centralization-those from less-centralized political parties and from parties not affected by restrictions on free parliamentary voting - have a low or non-existent incumbency disadvantage.