Preliminary and Incomplete Draft

We consider a symmetric information voting model where a group of uninformed voters must collec-tively choose a policy. An individual (information controller) can influence voters ’ choices by designing the information content of a public signal. We characterize the controller’s optimal signal, and how it varies with the electoral rules and the distribution of voters ’ preferences. We show that under a non-unanimous voting rule the controller can exploit voters ’ heterogeneity by designing a signal with realizations that target different winning coalitions. As a result, under simple majority voting rule, a majority of voters might be strictly worse off due to the controller’s influence. We characterize voters’ preferences over electoral rules in anticipation of the controller’s influence. We provide conditions for a majority of voters to prefer a supermajority (or unanimity) voting rule, in order to induce the controller to supply a more informative signal. JEL classification: D72, D83