I must respectfully disagree. In the last several elections we've been treated to a number of analysts, notably Nate Silver, who used polls, and specifically poll averaging to predict results and their predictions have been very accurate.
Any one poll can be off, but averages tend to make the data more accurate.
It's still a long way till the first vote, but I believe the rough outlines of the race are very clear. We do know that successful candidates are always near the top of the polls, not stuck under 5% perennially.
Nate Silver has another article on his site explaining that Christie is not going to be the nominee. It's based on favorabilty and familiarity polling. Most people know Christie, and most don't like him. Stick a fork in him, he's done.
I will bet you that none of the under 5% candidates will finish in the top three places in the first three contests: Iowa, New Hampshire, and South Carolina. Specifically that's Perry, Kasich, Santorum, Graham, Jindal & Fiorina. The only one who might give me some worries is Graham, as a favorite son in South Carolina. But even if he got lucky there, it's the end of it for him.