The article identifies two schools of thought on why Quebeckers choose to support or oppose sovereignty - the rational choice approach that has focused on individuals' assessments of the collective costs and benefits of sovereignty for the Quebec economy and the French language, and the socio-psychological approach that has focused on variables such as resentment, feelings of status denial, ethnic grievances and self-confidence. It has been difficult to resolve disputes between the two approaches due to weakness in available data and a lack of a comparative approach amongst scholars. Using a data set explicitly designed to compare the two schools, this article examines whether previous researchers' conclusions hold even when concepts are operationalized in different ways and when models are specified using different variables. The author examines five general dimensions: the state of the economy, the state of the French language, the state of federalism, respect and recognition, and the perceived quality of relations between English and French speakers. The major substantive conclusion is that the previous scholarship on the motivations for vote choice have significantly overestimated the importance of assessments of the French language, significantly underestimated the importance of assessments of whether Quebeckers are respected and recognized within Canada, and have also underestimated the importance of assessments of federalism and the quality of relations between linguistic groups. These conclusions hold for even the most ambivalent voters.