I think Harris will likely be perceived as doing better than Trump (though I think both will be pretty bad). I don't think the polls will register much of a difference. My heuristic is trying to imagine what would happen if the Harris we saw in her debate with Mike Pence were to meet the Trump of the last debate. And I think Harris comes out looking better in that line-up. I think Harris battled Pence to a tie; Trump won by default because of his opponent's age issues, but the worst parts of that performance were really bad. Harris will come well-prepared. Her answers won't be very substantive, but she'll avoid major pitfalls. Trump will come out swinging, but he will lack discipline. He'll continue to find himself unable to say the things he needs to say about the last election, the peaceful transfer of power, and the 1/6/21 riot to avoid sounding like a psychopath. No amount of debate prep can train that fatal weakness out of the man, and the Democrats will successfully exploit that on Tuesday, I predict.