" The number of delegates to the Electoral College would be determined not by a state’s population but by the number of its representatives in the House. That is, the size of a state’s representation in the Electoral College was determined by the rule of representation—one member of Congress for every forty thousand people, with people who were enslaved counting as three-fifths of other people.10 The Electoral College was a concession to slave owners, an affair of both mathematical and political calculation. "

― Jill Lepore , These Truths: A History of the United States