Following approval of a referendum in 1993, New Zealand replaced its first-past-the-post electoral system with proportional representation (PR). Although support for PR was initially high, less than a third expressed support for the new system a year and a half after its implementation. We examine two explanations for this decline. One theory assumes that dissatisfaction with the new system is the result of a growing alienation with politics, exacerbated by an unpopular coalition government that voters neither expected nor desired. Another theory assumes that evaluations of the new system are mediated by a preference for coalition or single party government. Our results indicate that a preference for single party government, guided primarily by partisan self-interest, has the largest impact. Nevertheless, negative evaluations of the performance of the coalition government helped contribute to a loss in support for PR suggesting that government performance can affect citizen's evaluation of political institutions, particularly when systems undergo radical change.