As we've seen so often lately, the makeup of the Supreme Court is a major factor in charting the course of our history.  The battle to replace Scalia is guaranteed to be both protracted and very, very nasty.  

A GOP controlled Senate which "early-on" stated openly that it was dedicated to making President Obama's Presidency a failure, will NEVER approve an Obama nomination.  The stakes for both the presidential and senate races have just risen significantly.