Some states like Florida are good about publishing voter reg states by county pretty frequently, meaning we have a live dataset to try and analyze. What's nice about this data is unlike a poll which is hypothetical and may be flawed, these are real numbers.
However, there are some things that can muddy the waters when it comes to voter reg stats.
One thing is the lag - many people who are essentially safe D/R voters federally right now are currently registered with the opposite party, and many of these voters are only changing their registrations now. Good example is FL where many of the panhandle counties that have been safe R federally for quite a while have only recently flipped to being R plurality/majority.
Another variable is registered Independents/NPAs. This block isn't necessarily a 50-50 block like many assume - there is a lot of evidence that in many states like NV and NC, the increasing Independent/NPA registration is largely powered by D-leaning voters. This might also mean Ds relatively poor numbers in new regiristrations relative to Rs in Nevada might not actually be so bad.
What do ya'll think?
Voter Registration Data is nice.
However what's more important is the Early-In-Person + VBM Data that's going to be available close to an Election and Florida does best in there.
I knew Trump would win Florida in 2020 because of the combined Early-In-Person/VBM Florida published. At the end of Early Voting Democrats had a 100,000 lead over Republicans. I knew this wasn't going to hold through Election Day. Also the Miami-Dade County Data where D's only had a 60,000 Ballot Edge heading into E-Day was enough for me to extrapolate that Trump would be doing much better in 2020 compared to 2016.
I wish every State would run 10-Minute Intervalls on the Early and E-Day Vote like FL does.
These kind of Data Sets does allow you extrapolate and you can have an 80-85 % Degree of Confidence who wins the State.
Finally you can already be sure of that Biden won't do as well with NPA/Independent Voters in FL and Nationally in 2024. He won them by Double Digits in 2020.