RE: Whoever thought of it was a genius for his time.
Without the electoral college, we would not even have a United States of America. The smaller states refused to join the union for fear that their voices will be minimized by the bigger states of NY, PA and MA. The Electoral College was developed in order to address the concerns of the other states.
And of course, the Constitution was approved conditionally with the Bill of Rights to be added.
It didn't take all 13 states to make the Constitution effective.