The Constitution provides for a federal republic because if the U.S. were a direct democracy, a few large states could elect a president by themselves. That would be a disservice to the remainder of the nation.
The Electoral College doesn’t reflect one-man-one-vote because it wasn’t designed to. It's a blend of the pure democracy of the U.S. House (with one elector per U.S. representative, each of whom represents about 750,000 Americans today) and our federal system.
As a nation, we are both a democracy and a federation of states. The Electoral College was designed specifically to prevent the tyranny of big states over small states, as was the U.S. Senate, which affords all states, large and small, equal representation.
If we did away with the Electoral College in favor of the national popular vote, the election would still be decided in a handful of states — populous states such as California and New York. Voters in small states would be completely disenfranchised. Candidates would never have to campaign in small states.
The 2000 and 2016 presidential elections are only the fourth and fifth where the winner lost the popular vote, out of 58 contests, with the other three being elections in the 19th century. That means the Electoral College is batting 53 for 58.
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