The statement that best analyzes how James Madison contributed to the U.S. political structures and decision making today is:
Madison wrote the Virginia Plan, which served as the basis of debate over representation in Congress at the Constitutional Convention.
This statement accurately captures Madison's significant role in shaping the structure of the legislative branch and his influence in the foundational debates that led to the creation of the U.S. Constitution. The Virginia Plan proposed a system of representation based on population, which was a crucial point of discussion during the Constitutional Convention.