Over the last week, I’d say Romney has hurt his chances in November more than Newt Gingrich or Rick Perry has. The Bain attack was bound to come this summer and fall, and I’m skeptical that voters will find the attack much more compelling from Obama if he can also name-drop Newt. Romney’s pink-slip and I-like-being-able-to-fire-people comments were more worrisome, because they suggest weaknesses in the candidate’s ability to make his own case and to defend himself. (His weak moments in Sunday morning’s debate, though less important, added to this impression.) Yes, the fire-people comment was taken out of context, but that happens in presidential campaigns (and of course Romney has done some of it himself). I still think that Romney is the best bet of the bunch–see NR’s latest issue if you want to know my reasons–but he can ill afford more such mistakes. Not because they will cost him the nomination, but because they will weaken him against Obama.