President Donald Trump is trying, and failing, to steal the 2020 presidential election won by Democratic rival Joe Biden by pressuring Republican state and local officials in states Biden won to override the will of the people, block the certification of their state’s election results and name Trump the winner.

This is only possible because of the Electoral College.

In 2016, the Electoral College allowed Trump to win the presidency in spite of losing the popular vote by nearly 3 million votes. Now Trump is attempting to use the system for a scheme to overturn his loss in the electoral vote and attack the bedrock of American democracy, the peaceful transfer of power.

The 2020 presidential election is not remotely close in the national popular vote. Biden leads Trump by nearly 6 million votes, or 3.8 percentage points. That percentage margin is the same as President Barack Obama’s 2012 reelection victory and is expected to grow further as hundreds of thousands of mail-in ballots in New York are counted.

The Constitution requires that the president be elected by a majority vote in the Electoral College, which awards 535 electors to states based on their number of members of Congress and three to the District of Columbia. This means that presidential elections are often fought over just a small handful of swing states where both parties just so happen to be competitive.

That handful of states in 2020 included Arizona, Georgia and Wisconsin, where Biden won by a combined total of less than 50,000 votes. A reversal in those three states would have created a tie in the Electoral College, sending the election to the House of Representatives, where Trump would have prevailed even as Biden triumphed in the popular vote by millions. (The House votes by state, and Republicans control the majority of states in the chamber.)