One proxy for voter enthusiasm is small donors numbers. I still see August as most recent numbers and we can compare and contrast to how 2020 Biden Trump numbers looked. Open secrets.
In 2020 Trump was 49% small donors while Biden was 39%. As of 2024 August’s numbers Trump is down at 32% and Harris 42%. And that’s with Harris’s total numbers being substantially higher so in absolute term more impressive.
The numbers of of strong approval and disapproval are another proxy for enthusiasm. From a recent YouGov discussed here elsewhere:
She seems to be ahead in those strongly voting FOR her and way less in those motivated to vote AGAINST her compared to Trump.
Hopefully this translates to turnout.