Michigan will determine whether Mitt Romney’s superior money advantage and bigger organization is worth anything. It’s to these two qualities that insiders cite when explaining why Romney can weather these challenges from Santorum and Gingrich. But Romney’s losses show the obvious limitations to this firewall. Money and organization don’t help much in contests where movement conservatives dominate. They don’t help in Michigan, which is not as hospitable as Florida was but has a more diverse electorate than the caucuses in Colorado and Minnesota. Right now Romney advisers still seem confident they will pull it out in Michigan. And if past is prologue, a win will revive his fortunes, diminish the talk of a brokered convention, and set Romney up for his next near-death experience on Super Tuesday.