She is not unworkable, in terms of pressure. The bigger/equal hurdle would be Biden himself. I think it's safe to assume that if Biden can be moved to support this, Feinstein will be mopped up in the wave.
And the coming weeks will give any number of reasons for these Dems to re-evaluate their stances. The GoP can always be relied upon to show indecency and outrageous behavior when they have a goal almost at hand.