Democrats, as per @LarrySchweikart, tend to dominate early voting.
Blue collar Dems flipped to support Trump in droves in 2016.
The R registration numbers may be a reflection of this.
Perhaps the spike in early voting are D->R flips
How Republicans vote didn’t change, just who is voting as a Republican changed.
Seems to me like it wouldn’t be outside the realm of possibility for a lot of Democrat voters to decide they’re tired of losing to people from the left and right.
/end