I have Biden winning the black vote 81%-15% (4% third parties) so this is about right (considering Biden will win most undecideds). That would still represent a right-wing shift for black voters (as has been happening since 2012).
In fact there's a distinct possibility that black voters will swing right for the fourth consecutive election (2012, 2016, 2020 and now 2024). That could be enough to flip Georgia if white suburbanites don't trend further left.
I’d be surprised if it’s only +66. I do expect them to swing right though.
