Ellis indicates that "the truly effective centers of power were located in two political partnerships based on personal trust." Explain

The first of the partnerships would be the relationship between Adams and Jefferson. When they broke away from each other due to their differing beliefs (notably Jefferson's reservations about a central federal government), Jefferson forged another partnership with James Madison. At that point, the trust between Adams and Jefferson was destroyed. The relationship and problems between Jefferson and Adams are detailed in Gradesaver's summary and analysis of Chapter Five. I have provided the direct link below.

http://www.gradesaver.com/founding-brothers/study-guide/section6/