Infant mortality rates in the US exceed those in all other developed countries and in many less developed countries, suggesting political factors may contribute. Using annual time series on overall White and Black infant mortality rates in the US 1965-2010, we examined whether infant mortality rates varied across U.S. presidential administrations. Data were de-trended using cubic splines and analyzed using both graphical and time series regression methods. We found that, across all nine presidential administrations, infant mortality rates were below trend when the President was a Democrat and above trend when the President was a Republican. This was true for overall, neonatal and postneonatal mortality. Regression estimates show that, relative to trend, Republican administrations were characterized by infant mortality rates that were, on average, 3% higher than Democratic administrations. In proportional terms, effect size is similar for US Whites and Blacks. US Black rates are more than twice as high as White, implying substantially larger absolute effects for Blacks.