There are plenty of ways to do this. He could cancel or delay the election. He could declare himself winner, no matter the actual result. He could simply manipulate the election (he’s already doing so). There’s plenty of ways. But what’s most important and what people need to understand is, that all he needs are enough supporters, who believe him. He doesn’t need to convince the majority that what he’s doing is right. He only needs to convince his base. And they are heavily armed and basically members of a political death cult.
It has happened in so many other countries before. The USA is not special. It can happen there, too. It might very soon.
By the way, what if the military or the police keeps answering to him, even if he loses? Do you trust the American police to be on the side of law and reason? I don’t.
The very same president has manipulated an election before, he’ll try again. He might succeed.
And again, I’m not saying it’s going to happen, but it can. And there should be plans for a scenario like this. Because he doesn’t care about the constitution.
There is no warning sign of fascism or authoritanism the USA is not currently displacing.