If a Supreme Court justice retires or dies in the next two years…..

[Landslide Lyndon]

If Obama nominates a demonstrably qualified individual, especially if it's a woman or a minority (I have a hunch it might be Jacqueline Nguyen), then the Republicans will be in a bind because their obstruction will reinforce the worst stereotypes about them and will inflame the Dem coalition.

But let's see first how the national environment will be by then. If the polls are promising for the Republican contenders, then the senate will stall the process until the election.
But if Hillary continues to dominate like now, then who knows how they will react?

[Landslide Lyndon]

If Ginsberg or Breyer retire, I think Obama could probably successfully nominate one of the several judges that received unanimous or near-unanimous confirmation to the appellate courts. Nguyen seems like a good guess to me as well.

I understand that the urge to reject any Obama nominee and the pressure from the base will be enormous. But the optics of a bunch of old white guys refusing to even consider a young, qualified Asian woman will be terrible.
They will reinforce the worst stereotypes about the Republican party just when they are about to face the first female presidential candidate in history.