Murdered or natural causes is irrelevant at this point. The balance of power has shifted to slightly leaning left on the bench.
The bigger question in mind is, will the Senate stand their ground till Jan 3, 2017 and not approve a liberal Supreme Court Judge? Then there is a short window our President could do a Recess Appointment IF the DEM's take back the Senate between Jan 3, 2017 and January 24, 2017 when a new President is sworn in.
Mr. Obama has made "Recess Appointments" in the past while Congress was in session. He lost those appointments when his action was taken before the SCOTUSA.
My guess is that Sen. McConnell is a spineless piece of snail crap and will allow a nomination to go forward as the pressure mounts.