Most delegates in the U.S. Constitutional Convention in 1787 recognized the value of constitutional safeguards against excess democracy, or mob rule. The U.S. House of Representatives was to be the only democratically elected federal institution—the U.S. Senate, the U.S. Supreme Court, and even the U.S. Presidency were to be filled by the state legislatures, the U.S. President and U.S. Senate, and electors elected by citizens, respectively. The people were to be represented in the U.S. House and the State governments in the U.S. Senate. The Constitutional Amendment in the early twentieth century that made U.S. senators selected by the people rather than the governments of the States materially unbalanced the original design. In terms of the selection of the U.S. president by electors, the political parties captured them such that whichever party’s candidate wins a State, the electors there are those of the winning party. Even if the electors could vote contrary to the popular vote in a State, such voting could only be a rare exception given the party-control. Hence the electors have not been able to function as intended—as a check against excess democracy. The case of Russian interference in the presidential election of 2016 presents an additional use for the Electoral College, were it to function as designed and intended. Of course, this is a huge assumption to make, even just in taking into account the American mentality regarding self-governance.
The full essay is at "How American Presidents Are Selected."