Outside a polling place in the suburbs of Detroit, a shouting match between two women escalated into a parking-lot scuffle, ending with one of them shoved to the pavement.

At a community center in southern Florida, a middle-aged woman handing out Republican pamphlets reached frantically for her pepper spray as a man
supporting Hillary Clinton charged at her.

And in Pueblo, Colo., an Army veteran with a .45-caliber pistol on his hip and a notebook in his left breast pocket watched from outside the county election
office, scanning the people who came and went for signs of the fraud he was certain he would see.