Examining the Impact of Electoral Competition and Endogenous Lobby Formation on Equilibrium Policy Platforms

Abstract This paper formulates a mathematical model that combines the dynamics of interest group formation with electoral politics, involving office-seeking and corrupt political candidates and voting population with well-defined policy as well as ideological preferences. The analysis provides several interesting insights into the factors affecting lobby membership, free-riding incentives of citizen-voters and aggregate monetary donations garnered by lobby groups. Besides this, the paper also explores the impact of the formation of distinct lobby groups, the presence of swing voters and the corrupt practices or financial embezzlement on the equilibrium policy choice of electoral contenders. The findings reveal that more honest spending of campaign donations by electoral contenders reduces both the size of the lobby (or membership) as well as aggregate campaign contributions in equilibrium. In contrast, a rise in the fixed cost of organization is found to augment lobby membership along with the total amount of campaign contributions. In addition, a reduction in the level of electoral uncertainty as well as a rise in the ideological or swing voter density is found to increase the effectiveness of campaign contributions in raising an electoral candidate’s perceived popularity and, therefore, a smaller lobby group with lower aggregate donations is deemed as sufficient in influencing electoral outcomes. Moreover, the results indicate that a lower utility difference derived by the citizen-voters when comparing the two electoral candidate’s policy choices translates into smaller dispersion of the voters’ ideological bias, and consequently results in an increase in the size of lobby groups and their corresponding aggregate donations. As regards the choice of equilibrium policy, evidence of full policy convergence is not found in the case when citizen-voters of the two groups have separable preferences. In addition, policy equilibrium for a more realistic case in which the two policy platforms exhibit strategic interaction by reacting to each other has also been estimated with the help of simulations. Finally, this paper helps in categorically deciphering the influence of the median voter effect (or the centripetal force) and the distinct centrifugal forces in the form of lobbying effect, swing voter effect and the financial embezzlement effect on the equilibrium policy choice by employing different parametric specifications of the model.