Partisan Politics and Aggregation Failure with Ignorant Voters†

We analyze how voter ignorance effects competing candidates’ policy choices and election outcomes. We show that voter ignorance of policy positions has no effect in large elections provided voters know the preference distribution in the electorate. We then explore a model where voters are ignorant of policy positions and of the preference distribution. In that case limit equilibria (as the number of voters gets large) yield partisan politics (i.e., candidates may not adopt the median favored policy) and aggregation failure (i.e., voters may reject the median preferred alternative). These non-Downsian conclusions hold even when candidates have weak policy preferences and mostly care about winning the election. † Financial support from the National Science Foundation is gratefully acknowledged.