Multiculturalism has emerged to challenge liberalism as an ideological solution in coping with ethnic diversity in the United States. This article develops a definition of political multiculturalism which refers to conceptions of identity, community and public policy. It then analyses the 1994 General Social Survey and a 1994 survey of Los Angeles County to assess the contours of mass support and opposition to multiculturalism, testing hypotheses concerning the role of social background, liberalism–conservatism and racial hostility. The main conclusions are that ‘hard’ versions of multiculturalism are rejected in all ethnic groups, that a liberal political self-identification boosts support for multiculturalism, and that racial hostility is a consistent source of antagonism to the new ethnic agenda of multiculturalism. There is strong similarity in the results in both the national and Los Angeles samples.