I've watched this 10 times and laughed ever time:
Obama is saying that he has the power under the Constitution to nominate someone to fill the vacancy on the Supreme Court even in the last year of his presidency and that there's nothing in the Constitution that says he can't. Of course, the Constitution also provides that the appointment isn't complete until the Senate votes to confirm, and there's nothing that says that power must be exercised within a certain period of time. These are opposing powers and the present struggle is political, which the President surely knows. Part of the politics is making claims based on interpretations of the Constitution, and each branch of government tends to interpret its own power broadly. It's interesting to me to watch how the rhetoric plays out. I mean, it's temping to say "It's pretty fucking hard to find that in the Constitution." And it's hilarious to get as close as he did to saying that.