Does trading votes in national elections change election outcomes?

Although forbidden in democratic states a market for votes could improve efficiency. This paper examines the way trading votes will change the outcome of an election. A two-party model with two phases is presented. In the pre-trading phase the two parties set their agendas consisting of a direct subsidy and an income tax. In the trading phase voters buy and sell votes. On the basis of rational voter behavior and a given income distribution, it is shown that the outcome of the election depends mainly on how the selling voters are distributed among the voters.