MADISON HEIGHTS, Mich. - The Biden-Harris pep rally at a union hall here was thrown together quickly, not wanting Donald Trump’s visit to Oakland County the next day to go unchecked.

The two events could not have been more different, either in scale or in tone. A small community of Democratic activists came Friday, seeking the jolt of energy they felt their campaign lacked, and their anxiety was palpable, both for the difficulties of winning and the consequences of failure.