Which political scientific model of American politics says there is a tiny group of connected and wealthy Americans, totaling around 3000 in number, who are the real rulers of America?

Elite Theory

Explanation:

Elite theory, in sociology and political science, is a theory which intends to explain the relationship of a small minority of powerful individuals with the state. This theory contends that this group of highly influential figures dominates the decision making of a state and is almost always independent of democratic elections. It is able to do this because its members occupy coveted decision making positions such as on boards of mega corporations.