Why Joe Biden is gaffe proof:

Informational gaffes don’t hurt Biden because, whatever his imperfections, he’s generally seen as worldly and knowledgeable. Message gaffes don’t matter because, even if it’s a headache for the campaign, they make him sound authentic. (If he thinks the ad is “terrible,” that’s just his honest opinion!) And political gaffes don’t damage Biden because, well, he’s so darned congenial. Even John McCain likes him.