What do supporters of the Electoral College say?
“If [the Electoral College] be not perfect, it is at least excellent.” That is what Alexander Hamilton wrote in The Federalist Papers. He did not need to write much, since even the opponents of the new Constitution mostly agreed that the Electoral College was a good way to choose the President.
The mode of appointment of the Chief Magistrate of the United States is almost the only part of the system, of any consequence, which has escaped without severe censure, or which has received the slightest mark of approbation from its opponents. The most plausible of these, who has appeared in print, has even deigned to admit that the election of the President is pretty well guarded. I venture somewhat further, and hesitate not to affirm, that if the manner of it be not perfect, it is at least excellent. It unites in an eminent degree all the advantages, the union of which was to be wished for.
[T]he current Electoral College system respects states as the essential units in our compound republic, protecting their power and voice in presidential elections [and] respects the separation and balance of power and authority between the states and the federal government.
The resolution also points out that the Electoral College "ensures that the winning candidate has support from multiple regions of the country [and] that each state's electoral votes are awarded based on how the state's citizens vote."
The Republican Party, in its national platform, supports the Electoral College and opposes the National Popular Vote campaign. (The Democratic Party's national platform is silent on the topic.)
We oppose the National Popular Vote Interstate Compact and any other scheme to abolish or distort the procedures of the Electoral College. An unconstitutional effort to impose National Popular Vote would be a grave threat to our federal system and a guarantee of corruption, as every ballot box in every state would offer a chance to steal the presidency. We urge state legislatures that have voted for this proposal to rescind their approval.
In his book, Why We Must Defend the Electoral College, Save Our State's Trent England warns that attacks on the state-by-state process for electing the president threaten the Constitution itself.
The more fundamental risk is that the public adheres to the beliefs that underlie these attacks—that the Constitution is out of date, that the measure of an election is voter self-esteem, and that democracy is an end in itself. All those beliefs can as easily be turned against any of our constitutional checks and balances. The very idea of a constitutional republic is at stake.