Existing research has found a positive association between countries' level of democratic governance and the health of their populations, although that research is limited by the use of data from small numbers of high-income countries or aggregate data that do not assess individual-level health outcomes. We extend prior research by using multilevel World Health Survey (2002-2004) data on 313,554 individuals in 67 countries, and find that the positive association between democratic governance and self-rated health persists after adjusting for both individual- and country-level confounders. However, the mechanisms linking democracy and self-rated health remain unclear. Individual-level measures of socioeconomic status, and country-level measures of economic inequality and investments in public health and education, do not significantly mediate the association between democratic governance and self-rated health. The persistent association between democratic governance and health suggests that the political organization of societies may be an important upstream determinant of population health.