Justice Scalia has passed away. Now what?

Supreme Court Justice Antonin Scalia has passed away at the age of 79. President Barack Obama has nearly a year remaining in his term, so he will certainly send a nominee to the Senate. (He has already announced that he will.) The nominee will likely be so far to the political left that the Republican-controlled Senate will not confirm him. This will probably mean a 4-4 tie on a lot of Supreme Court votes. What will this mean?

Of course, Senator Harry Reid has sounded off:

The President can and should send the Senate a nominee right away. With so many important issues pending before the Supreme Court, the Senate has a responsibility to fill vacancies as soon as possible. It would be unprecedented in recent history for the Supreme Court to go a year with a vacant seat. Failing to fill this vacancy would be a shameful abdication of one of the Senate's most essential Constitutional responsibilities.

Note that Senator Reid says “unprecedented in recent history.” President John Tyler had a situation much like Obama's, where his term was coming to an end and the Senate kept rejecting his nominees, so the position remained vacant for more than two years. But Senator Reid has a point: a lot of cases will end up in tied votes if the vacancy remains unfilled. But given that President Obama may well nominate a left-wing extremist, the Senate obviously would have a difficult time confirming someone whose views are so contrary to theirs. It will be very interesting