We ask whether party competition improves economic and social well-being, drawing on evidence from the 50 American states for the period 1880–2010. Today, strident party competition and partisan polarization are blamed for many of the ills of national and state politics. But a much deeper political science tradition points to the virtues of competitive party politics. In this historical analysis, we find that states with competitive party systems spend more than other states—and specifically spend more on education, health, and transportation, areas identified as investments in human capital and infrastructure. We find that this spending leads to longer life expectancy, lower infant mortality, better educational outcomes, and higher incomes. Thus we conclude that party competition is not just healthy for a political system but for the life prospects of a state’s residents.