Northam is screwing up the dem plan to attack POTUS as a racist going in to the SOTU. If Northam holds out until then POTUS can enlighten the audience about Northam's abortion remarks, as only POTUS can.
If dems drive Northam out, thereby replacing him with Fairfax, they can claim racist high ground.
Northam has to have a lot of leverage to pee on all the big dogs' legs like he has.