Well, again, I have already laid out how or why Harris lose if she loses (which is very likely at this point)
The problem associated with that is that she don't really have enough time to campaign against Trump. That is all democrats fault, instead of selling her as a viable candidate and competent at her job, she was present as a replacement of an old guy which she followed since 2020, who the dem panicked and bump her up in his place.
I said the same thing after July when she was announced as replacement, and I said it immediately after she had that debate with Trump.
As for whether or not she had a chance, well, this election is not exactly one sided, and she did claw back a lot of voter that would have voted for Trump, just that it's not enough.