The next chapter in the tumultuous US presidential election plays out Monday, with voting in the Electoral College expected to officially confirm that billionaire real estate mogul Donald Trump will become the country’s 45th president.

Americans have known since early November that Trump would take over the White House when he is inaugurated January 20. US presidential elections, however, are not determined by the national popular vote, but rather by the individual outcomes in presidential balloting in all 50 states and the national capital city, Washington.

The popular vote winner in each state normally receives all of that state’s Electoral College votes, which are allotted in proportion to the state’s population.

Donald Trump is lashing out on Twitter in advance of the Electoral College vote. The president-elect says: ‘If my many supporters acted and threatened people like those who lost the election are doing, they would be scorned & called terrible names!’

The Electoral College is gathering Monday to formally elect Trump. GOP electors have been inundated with emails, phone calls and letters urging them to vote against Trump. And protests are planned across the country in state capitals where electors will meet.

In fact, Trump and his supporters have threatened people before. He frequently whipped up audiences at his huge rallies by railing against reporters, immigrants, Muslims and his critics. He repeatedly threatened news outlets with lawsuits. And, he and his supporters have bombarded his critics on Twitter.