Manchin has a problem right now. There's a SCOTUS nominee coming up and he has to go on record. If he votes no he may be toast in W.VA. But if he votes yes the dems may not be able to to stop the nomination.
Until we see what he does, no prediction in his case makes sense.
For a quantum mechanics analogy, he's Schrodinger's cat right now and the box is still closed. He's both alive and dead (politically) until that box opens, then he'll be one or the other.
Yes, the SCOTUS vote will be an acid test for several Rat senators. It will be very interesting to see just how they square this circle.