Story highlights Trump won the Electoral College

But he trails Clinton in the popular vote by about two million

Washington (CNN) President-elect Donald Trump alleged Sunday, without evidence, that "millions of people" voted illegally for Hillary Clinton and otherwise he would have won the popular vote. It's an unprecedented allegation by a president-elect.

Trump won the Electoral College and thus the White House, but the Democratic nominee leads him in the popular vote by about two million ballots.

"In addition to winning the Electoral College in a landslide, I won the popular vote if you deduct the millions of people who voted illegally," Trump tweeted.

In addition to winning the Electoral College in a landslide, I won the popular vote if you deduct the millions of people who voted illegally — Donald J. Trump (@realDonaldTrump) November 27, 2016

"It would have been much easier for me to win the so-called popular vote than the Electoral College in that I would only campaign in 3 or 4- states instead of the 15 states that I visited. I would have won even more easily and convincingly (but smaller states are forgotten)!" he added.

It would have been much easier for me to win the so-called popular vote than the Electoral College in that I would only campaign in 3 or 4-- — Donald J. Trump (@realDonaldTrump) November 27, 2016

states instead of the 15 states that I visited. I would have won even more easily and convincingly (but smaller states are forgotten)! — Donald J. Trump (@realDonaldTrump) November 27, 2016

This is the first time he has alleged voter fraud in his own victory and there is no evidence of any widespread voter fraud.

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