The way the obstructionists have set it up there’s really no way for Obama to lose on replacing Scalia. The entire premise of their gambit is that maybe, just maybe if they can run out the clock on the Obama presidency, then President Trump/Cruz/Rubio will get to nominate the successor, no doubt in his conservative image. But bless their hearts they are simple, stupid creatures playing checkers on a chess board.
Fact 1: for the first time in a long time, there’s virtually no way that Scalia’s successor could be more conservative then Mr. “The Constitution is Dead, Dead, Dead”. The next Supreme Court Justice named will be a moderate at worst. Possibly a liberal. Even if hell froze over and President The Donald named the next person, they would be an improvement over Scalia. But that’s not gonna happen.
Obama will name somebody soon who is eminently qualified and probably a non-ideological choice who would be a return to a less politicized court. The GOP will block and it will look bad for them, making the naming of a Supreme Court Justice a very concrete point next November.
The real downside of being rather delusional about, well, almost everything, the Republicans are not only overplaying their hand in regards to the presidential election, they are pretending that their handle on the Senate isn’t in mortal danger.
Fact 2: The GOP has 5 senators from blue states (Ayotte, Kirk, Toomey, Johnson, Portman) that were elected in the GOP wave of 2010 and have poor chances of surviving a presidential year challenge. The likelihood of decent to good Democratic turnout is probably enough to give the Senate to the Dems, and with that the Judiciary Committee.
So if they want to play this out and deny a moderate a seat on the bench, it might just allow the next president to put an actual lefty on.