Democracy Undone: Systematic Minority Advantage in Competitive Vote Markets Casella Alessandra author Columbia University. Economics Turban Sebastien author Columbia University. Economics Columbia University. Economics originator contributor text Working papers New York Department of Economics, Columbia University 2012 We study the competitive equilibrium of a market for votes where voters can trade votes for a numeraire before making a decision via majority rule. The choice is binary and the number of supporters of either alternative is known. We identify a sufficient condition guaranteeing the existence of an ex ante equilibrium. In equilibrium, only the most intense voter on each side demands votes and each demand enough votes to alone control a majority. The probability of a minority victory is independent of the size of the minority and converges to one half, for any minority size, when the electorate is arbitrarily large. In a large electorate, the numerical advantage of the majority becomes irrelevant: democracy is undone by the market. Economics Department of Economics Discussion Papers 1213-10 http://hdl.handle.net/10022/AC:P:15388 English NNC NNC 2012-12-06 11:57:16 -0500 2012-12-06 12:18:13 -0500 9391 eng