Allocation of lobbying efforts under political uncertainty

Résumé

We study a simple influence game, in which a single lobby may manipulate the decision of a legislature via monetary offers to one or more legislators. The legislators care both about the social welfare and political contributions. We study how the legislators' preferences and the lobby's willingness to pay influence the final outcome and the offers. When the lobby's willingness to pay is high enough, the lobby ensures the necessary support by taking full control over a minimal winning coalition of legislators. On the contrary, when it is low, the lobby can ensure only uncertain support, and it may be optimal to disperse the influence over more legislators. We show that the higher is the lobby's stake, the less legislators it tries to influence, although its total expenditures grow.