—If Barack gets more liberal justices on the court, it is GAME OVER.—
Congress has to approve them. If republican controlled, they can always Bork them.
The Senate approves them. And even if they wanted, they can't stop them all. You can maybe stop one or two really bad Supreme Court picks, but eventually the GOP would look petty and have to bow to public pressure. It gets harder and harder to stop them after blocking the first. If Obama wins re-election, the Supreme Court is going to be decidedly more leftist. Think of all the decent 5-4 decisions, and just assume they are going to go the other way. At minimum Hussein will be replacing Ginsburg, but one or more of the conservatives might get sick and die and then he replaces them too.