Here is something to think about..
The new congress takes office on Jan 3rd
The new president takes office on Jan 20th
What if.... Obama nominates someone... the republican controlled Senate blocks a vote on them, Trump wins the election, but Republicans lose the Senate. A Democratic controlled Senate takes over on Jan 3rd, 17 days before Trump is sworn in and rubber stamps ANY nominee Obama has made before Trump can withdraw the nomination on the 20th after taking office.
Heck Ginsburg might even resign during that period and Obama and a Democratic Senate could replace them both in one fell swoop as a big FU before leaving office.
Could Republicans filibuster in that case?