Are early voting numbers predictive of anything?

[Dr. Jack]

This is the first election in a long time where I feel like I really don't know what is happening or where things are headed. The polls are somewhat anemic for the Democrats and are pointing to very close results for both chambers of Congress. That's kind of what I assume will be the results and since polls the last few cycles have underestimated the Republicans a bit, I'm a bit pessimistic when looking at polls.

But then I see the special election results over the summer where the Democrats over performed their polls by a shocking degree. And there are reports of massive early voting turnout. These things are giving me some pause and make me wonder if the polls are significantly underestimating the Dems. However, I've also been here before. We are all susceptible to grasping at straws before an election in an effort to show ourselves that things might not be as bad as they look. I remember in 2016 seeing reports that there was a high level of interest in voting among Democratic constituents in Florida and people saying that was proof that Trump would lose the election badly. That clearly didn't happen. And I think we all remember the mirage that was a Blue Texas in 2020.

So today it's "look at these early voting numbers! Ignore the polls! Blue wave incoming!" among many Dems online. But does that actually prove anything? Is that actually a sign of "oh shit, something big is happening" or are people just deluding themselves by finding one piece of seemingly good news that is actually meaningless?