Survey data from the preconvention waves of the 1980 National Election Study are used to estimate the effect of expectations about who will be nominated on respondents' own preferences. The results confirm the conventional belief that bandwagons play an important role in nominating campaigns; at the same time, they suggest that the dynamics of the nominating process may be more subtle than simple bandwagon models would indicate. First, preferences are strongly and consistently projected onto expectations, making the relationship of central interest a reciprocal one. Second, the bases of candidate choice appear to change systematically with political circumstances. In close, volatile campaigns, support for bandwagon candidates (like George Bush in early 1980) is based largely on favorable expectations and on relatively general, diffuse political evaluations (e.g., “leadership”). By comparison, when expectations about the nomination are very one-sided, their impact on preferences approaches zero, and more specific, substantive political evaluations become increasingly important.