I only watched part of this, but I tentatively conclude the following:
If there was a winner, it was probably the fly that landed on Pence's head.
Other than bolstering the fly's political career, this will have little or no political effect. Polls coming out over the next few days might prove me wrong, of course. And I am hardly the typical swing voter (or, at this point, even a swing voter at all). But I suspect this debate will go down the memory hole pretty quickly.
Both Pence's evasion on accepting the election results and Harris' on court-packing were reprehensible. But both will probably get away with it (or at least not suffer any more damage than has already been inflicted by their respective bosses' similar evasions).
I continue to believe Biden is a lesser evil than Trump.