Using an experiment embedded within a representative survey, this study examined the interactive effect of party identification and risk/benefit perception on public opinion about biofuels. Democrats tended to be more supportive of biofuels than Republicans. However, the effect of party identification on opinion about biofuels varied when individuals considered the risk/benefit of biofuels in different domains. Individuals who reported greater affiliation with the Democratic Party were likely to support funding biofuels research when primed with the economic risks or the social/ethical benefits of biofuels. For those who considered the social/ethical benefits of biofuels, more self-identified Democrats were likely to support biofuels production and use. However, more self-identified Democrats were less supportive of biofuels production and use when they considered the political risks of biofuels. Implications are discussed.