Federalist Paper No. 68
….
"It was desirable that the sense of the people should operate in the choice of the person to whom so important a trust was to be confided. This end will be answered by committing the right of making it, not to any preestablished body, but to men chosen by the people for the special purpose, and at the particular conjuncture."
Translation: The people should have influence in whom becomes President.
"It was equally desirable, that the immediate election should be made by men most capable of analyzing the qualities adapted to the station, and acting under circumstances favorable to deliberation, and to a judicious combination of all the reasons and inducements which were proper to govern their choice. A small number of persons, selected by their fellow-citizens from the general mass, will be most likely to possess the information and discernment requisite to such complicated investigations."
Translation: It is necessary for educated and intelligent men to actually choose who becomes President.
"It was also peculiarly desirable to afford as little opportunity as possible to tumult and disorder. This evil was not least to be dreaded in the election of a magistrate, who was to have so important an agency in the administration of the government as the President of the United States. But the precautions which have been so happily concerted in the system under consideration, promise an effectual security against this mischief. The choice of SEVERAL, to form an intermediate body of electors, will be much less apt to convulse the community with any extraordinary or violent movements, than the choice of ONE who was himself to be the final object of the public wishes….
Translation: Transitions of power are messy and sometimes violent. The EC reduces these problems by removing popular opinion from directly electing the President and dividing the electoral college among the States. This system avoids the potential of extremist pressures from popular opinion on the election process.
"Nothing was more to be desired than that every practicable obstacle should be opposed to cabal, intrigue, and corruption. These most deadly adversaries of republican government might naturally have been expected to make their approaches from more than one querter, but chiefly from the desire in foreign powers to gain an improper ascendant in our councils. How could they better gratify this, than by raising a creature of their own to the chief magistracy of the Union? But the convention have guarded against all danger of this sort, with the most provident and judicious attention. They have not made the appointment of the President to depend on any preexisting bodies of men, who might be tampered with beforehand to prostitute their votes; but they have referred it in the first instance to an immediate act of the people of America, to be exerted in the choice of persons for the temporary and sole purpose of making the appointment…
Translation: Established political bodies tend to vote their own interests. By creating a temporary group of electors through the popular vote, it was hoped this would be avoided.
"Another and no less important desideratum was, that the Executive should be independent for his continuance in office on all but the people themselves. He might otherwise be tempted to sacrifice his duty to his complaisance for those whose favor was necessary to the duration of his official consequence. This advantage will also be secured, by making his re-election to depend on a special body of representatives, deputed by the society for the single purpose of making the important choice. "
Translation: Because the body of electors is temporary in nature and dependent on the popular vote, the President has little incentive to bribe or pander to electors.
[Next section outlines the technicalities of the EC, I'll skip it as it doesn't explain its purpose]
"The process of election affords a moral certainty, that the office of President will never fall to the lot of any man who is not in an eminent degree endowed with the requisite qualifications. Talents for low intrigue, and the little arts of popularity, may alone suffice to elevate a man to the first honors in a single State; but it will require other talents, and a different kind of merit, to establish him in the esteem and confidence of the whole Union, or of so considerable a portion of it as would be necessary to make him a successful candidate for the distinguished office of President of the United States. It will not be too strong to say, that there will be a constant probability of seeing the station filled by characters pre-eminent for ability and virtue. And this will be thought no inconsiderable recommendation of the Constitution, by those who are able to estimate the share which the executive in every government must necessarily have in its good or ill administration….
Translation: By decentralizing the process among the states, it becomes more difficult for a demagogue to rise to power.
[Last sections deal with the VP, and is not relevant]
Now, clearly there are some things to discuss.
a) The Federalist Papers are not official documents such as the Constitution. However, they are the arguments Constitution's writers used persuade the states to ratify it. As such, they are the closest and clearest insight into how these men intended our government to work and why they constructed it as they did.
b) The Constitution and the arguments presented above come from an 18th century reality. Our reality has a different form. The threats to representative democracy have a different form. But the underlying premises and philosophy: the importance of limiting centralization of power and the danger of extremist mass politics- are still relevant today. In fact, the contemporary arguments for and against the EC are still within the same framework they were over 200 years ago during the original Constitutional debate.
c) It is true the American government's form has changed since 1789. After the Civil War power began to shift away from the states and toward a larger and more active Federal government. Prior to 1865 Constitutional amendments limited the Federal government's power (the only exception being the 12th, which corrected election procedures). Afterwards amendments began, correctly, to extend or clarify Federally protected civil rights to former slaves, minorities, and women (13-15, 19, 24, 26), correct deficiencies in the Constitution (20, 22, 23, 25, 27), or expand the established powers of the Federal government (16, 18/21).
Now if you didn't notice, one amendment hasn't been mentioned. Amendment 17 changed the election of senators. Prior to its passage, senators were not elected by a state's citizens but rather appointed by state legislatures. That is because the Senate was originally intended to be a check on the influence of popular opinion, which was already represented by the House of Representatives. Like the electoral college, the Senate was intended to be insulated from the pressures of popular opinion. And this is why the Senate was given authority to do certain things considered susceptible to popular extremism, such as foreign policy and the approval of Federal judges.
That is the other big change in American government. Originally the Constitution was intended not only to provide a series of checks and balances between the branches of government. but a series of checks and balances between the influence of public opinion and serious, deliberation by the "qualified". As time has gone on, Americans have made changes to the government which favor far more direct and democratic participation in the government than was originally intended. The electoral college is an artifact of the original vision
While the electoral college is somewhat of a holdover from a previous era, I think its importance has changed rather than disappeared.
And I believe that because I entirely disagree with the premise that no one cares about Montana voters. Trump definitely cared about Montana voters. And Idaho voters. And Alaska voters. And Wyoming voters and Dakotas voters and voters in Maine's Second Congressional District. Without them, he would not be President elect.
You know which voters no one cares about? The 4.5 million California voters who chose Trump. And the 2.7 million New York voters who chose Trump. And the 3.8 million voters who chose Clinton in Texas. No one cares about them, because the respective candidates had no chance in those states.
If we scrapped the electoral system and went with a straight popular vote, no one would care about any of the voters living outside the major cities in large states since people in those areas make up a majority of the population. We would have a system where Presidential candidates pandered to the interests of urban voters and professional classes while completely ignoring the issues and interests of people occupying the vast majority of the land area in this country. People living in Montana would never see a President who needed to pursue policies ensuring a good and improving quality of life there. While Congress would halt the decline into serfdom, over time they would become peasants working for the interests of people living in New York, LA, and Chicago.
That is exactly the type of situation the electoral college was intended to prevent, even if the way it prevents that from happening today is different how it was originally supposed to do so.