Summary:
Flip
After Obama won the 2012 presidential election, Trump, under the mistaken impression that Obama won the electoral college but lost the popular vote, stated:
The electoral college is a disaster for a democracy.
— Donald J. Trump (@realDonaldTrump) November 7, 2012
Flop
In 2016, after Trump won the presidency due to the electoral college but lost the popular vote by a historic margin, Trump had a change of heart, stating:
The Electoral College is actually genius in that it brings all states, including the smaller ones, into play. Campaigning is much different!
— Donald J. Trump (@realDonaldTrump) November 15, 2016