1. Late start. Perry has spent nearly three decades in elected office and sometimes looks like a rookie on the campaign trail — or, more accurately, the debate stage. Christie had never held elected office before winning the governorship in 2009 and, although he has done a remarkable job of building his national reputation, has never been tested under the sort of spotlight that would shine on him if he ran. The struggles of Perry, former senator Fred Thompson (R-Tenn.) in 2008 and retired Gen. Wesley Clark in 2004 make clear that running for president requires skill that even most longtime politicians don’t possess.

2. Money. Yes, Christie could put together an impressive first month — or even first quarter — of fundraising. But the true giants of cash collection are those with staying power, the candidates who are able to get beyond the first $10 million (or so) and into the range of $35 million to $50 million. It’s not clear that Christie has that second gear or whether there are enough uncommitted big bundlers — the people who can donate and get hundreds of their friends to do the same — left for him to even try.