The Electoral Collage part of the U.S. Federal System of governance, and certainly an integral part of the ‘federal’ nature of the U.S. system; part of the original compromise to recognize the important role of States within the republic.
However, due to recent electoral results (see Presidential election of 2000 and 2016 – where the winner of the Electoral Collage did not also win the popular vote), there is a coordinated effort on the part of some States to ‘change’ it. Twelve States so far (soon to be 13) have passed legislation that would award their electoral college votes to the winner of the national popular vote (see National Popular Vote bill)
Feasibility (needs another 13 states to join the cause in order to come into effect) and constitutionality (states can’t compel electors to vote in a certain way) aside, it certainly creates momentum and pressure for some kind of reform of the electoral college.
Also, read Edward B. Foley article at Politico: An Idea for Electoral College Reform That Both Parties Might Actually Like, where he makes an argument for going back to the original reform of the 12th Amendment for awarding electors to the winner of the majority of the votes in a State (and not just the plurality – as is the case now).