Once again, the election results will have to speak loudly as they did last year. Mitt Romney was supposed to deliver his "home state" of Michigan last year, which didn't happen, same with Ryan in Wisconsin and to a lesser extent, Romney was supposed to do well enough in Massachusetts for Scott Brown to survive. None of that happened. At some point, there has to be a realization that Republicans aren't winning blue states just because they live in them.
Romney had no connection to Michigan other than his father, who most people not been alive or old enough to remember.
By 2012 Romney was an ex-governor of an extremely blue state going on six years. Many people no longer thought of him as Mitt Romney, Governor of Massachusetts, but Mitt Romney the Republican.
Christie on the other hand will be the incumbent governor of a fairly blue state, with most likely decent favorables.
Two totally different scenarios.