I listened to a conversation between historians Heather Cox Richardson and Joanne Freeman about feelings about the election today. They concur that the shifting moods happen (fearful of the outcome buoyed with occasional feelings of euphoria about Harris winning).

Apparently a lot of the "polls" we're hearing cited these days are bogus, they fast things promoted by the GOP and inserted into newsfeeds or into poll result sites to make it look like Trump is ahead. There were 30 of these added recently that had that effect. All of this, they note, is more attempts to scare voters out of participation.

Every vote counts. Ignore the polls.