White racial identity is central to whiteness studies. In order to further explore this key concept, this research uses new national survey data to model determinants of white racial identity. This article analyzes how prejudice, views on diversity and beliefs about America impact the importance of racial identity for whites. The data I use come from the American Mosaic Project Survey, a nationally representative, telephone survey (N = 2,081). This research adds to previous work in whiteness studies by using national survey data to measure and analyze white racial identity. This research also makes an important methodological contribution to race relations research by bringing concepts from whiteness directly into the arena of large-scale survey research. Finally, I discuss the duality of white racial identity in terms of its defensive and progressive components and the implications of this duality for future research. (Contains 4 tables, 1 figure and 6 notes.)