This is an outside shot at best.Just look at the reactions of some people on this forum,whom you'd think would support a candidate who wants a return to constitutional government."He can't win" is the reason most think he can't win,"so I won't vote for him",and,"He won't be able to implement those policies",so I won't vote for him.
And if he should win the nomination,believe me,they won't be squealing,they'll all have "been with him from the git-go".