https://theintercept.com/2016/11/28/donald-trump-first-sore-loser-elected-president-united-states/
"at a moment when he mistakenly thought Barack Obama had received fewer votes than Mitt Romney but had won reelection through the Electoral College — Donald Trump revealed a few things that we need to recognize right now. First, that this is a man who is easily confused or misled by the news he consumes from television or the internet. What Trump was referring to in his tweet, posted shortly after the polls closed on the West Coast, was the fact that Obama had been declared the winner by the news networks as soon as he was projected to secure a majority of the electoral votes by winning Ohio. At that moment, before almost any votes had been counted in California, Trump was baffled and outraged by the numbers he saw on the screen, which showed that Romney was then nearly a million votes ahead of Obama in the national popular vote count. “He lost the popular vote by a lot and won the election,” Trump wrote at the start of a Twitter tirade against “the phoney [sic] electoral college,” he would later delete. Not long after Trump’s Twitter eruption began, Obama pulled ahead in the popular-vote metric too, and he would go on to win a majority of the popular vote, defeating Romney by nearly five million votes, 51.1 percent to 47.2 percent. Beyond impetuousness, an inability to proof-read, and a shaky grasp of how elections work, what Trump’s tweet from four years ago reveals most clearly is that he thinks one word describes a presidential candidate who gets fewer votes than his rival: loser. With that in mind, it is not hard to understand Trump’s increasingly desperate attempts to spin his legally insignificant but politically embarrassing status as a president-elect who got 2.3 million less votes than his opponent, Hillary Clinton. The fact that Trump managed to get just 46.4 percent of the vote, securing a smaller share than Clinton (48.2 percent), as well as Romney — whom he had mocked for losing to Obama — clearly disturbs him, since he continues to bring it up, and make excuses."
