The election Chaos in Detroit that happened in 2020 may happen again as elections become more contentious with threats of violence. (NBC News)

At 10:04 a.m. the day after the 2020 election, President Donald Trump tweeted he was “leading” in the vote count in several “Democrat run & controlled” states — until, that is, “surprise ballot dumps” took those leads away. The implication that something nefarious was happening was categorically false. But primed by months of Trump’s baseless warnings about massive voter fraud and his false claim hours earlier that he’d won the election, Michigan Republicans answered the call.

They hurried to the convention hall in downtown Detroit, then known as the TCF Center, where more than 170,000 mail ballots in America’s largest majority-Black city were being counted. Millions had voted by mail for the first time in 2020, and the new processes in Michigan seemed foreign to them.

What followed was chaos. Trump supporters furiously alleged a campaign of fraud when none existed. When officials declared that the room was over capacity and stopped letting Republican and Democratic poll observers in, Trump’s backers felt their fears were validated: They started arguing with police and election officials, banging on windows and chanting “stop the count” outside a room of poll workers tabulating military ballots. By Ryan J. Reilly and Jane C. Timm ‘NBC News’