yes, they can do it, and they are SUPPOSE to do it....that's what the constitution says and that's how hamilton and madison created electors to be.... make their own decision on who to vote for..... not even coordinating with other electors in their State, but an informed, individual, decision....not by party, not by popular vote but they alone were to make their own individual decision.
Then politics got involved, and electors figured out they could have more power if they colluded together on who to pick as their candidate...and it's been all downhill since then...
ONE MAN, ONE VOTE....every elected position in the USA is picked that way....governors, senators, congressmen, legislators, county clerk, sheriff, school board members etc....
except our President.... it's bull crud.
IF TRUMP had won the popular vote but Hillary won the electoral vote, Trump would be tweeting from the rafters, the election was rigged, the system is rigged....
when wisonsin gets 3 electors for 500k citizens, and california with 39 million citizens gets 55, then the citizens in their state's vote does not count equally with a citizen in Wisconsin....that's simply not right, not fair, not just. one man, one vote against another man's vote, should be equal
if calif had the same proportion of electors as wisconsin citizens get, california would have 195 electors, not the 55....
it's stupid and highly unfair.