The Michigan Model is a theory of voter choice, based primarily on sociological and party identification factors. Originally proposed by political scientists in the 1950s at the University of Michigan's Survey Research Center, it looked to explain voting behavior in terms of a voter's psychological attachment to a political party, which would be built up over a period of many years.
According to the model, this party attachment is generally stable, formulated by outside social influences, including parents, family members and others in one's sociological spectrum. However, in recent years, the model has been challenged by spatial and valence models, forcing proponents to reconsider the long term implications of party attachment. Critics claim that the Michigan model exaggerates the assumption that party identification is cemented by circumstances, but rather that party identification can change in light of a party's performance or other circumstances. The model is only applicable to american "winner-take-all" systems, as lack of choice contributes to small chances for Partisan ID to change. The model most famously appeared in The American Voter.
The Funnel of Causality:
The model relies heavily on early attachment to parties, through the Funnel of Causality. This shows long term effects such as: Sociological Characteristics (Race, ethnicity, gender and sexual orientation), Social Status Characteristics (Social class & Occupation), and Parental Characteristics (Values and Partisanship). These factors go on to create Party Identification which is largely static within individual voters. And it is through an individuals partisan identification that short term choices, such as Candidate Evaluation and Issue Perceptions are created.