It's inevitable, tonight, that the 47% will be mentioned.
Here's what I'd say:
"Mr. President, that 47% of the country that doesn't pay taxes? That's a national disgrace. It's a disgrace that 47% of us aren't making enough money to pay even a small amount. But that's on you, sir. With joblessness higher than it's ever been, the economy sputtering, and federal spending out of control, no wonder there are so many people struggling to get by. What I don't understand is, why you think I should be the one apologizing. This is on you, Mr. President. And you should be ashamed."
Or, you know, you could just repeat what the smartest and most adroit political mastermind alive said yesterday: (Huge H/T to the great Jim Treacher)