Hi tkc,
Huntsman isn't a Republican in the modern sense.
Romney cannot win. He has a maximum of 25%. After 4 or 5 changes in the leadership of the race, he is always the wallflower. That means the Republican voters are not going to choose him as their dance partner.
If folks were going to move his way - if he was one of the mobile voters' top five candidates - he would have been accruing votes as others lost theirs. But that hasn't happened.
The obvious conclusion. Like Ron Paul, he has a loyal following, but it is capped at a certain number. The rest of the Republican electorate have a strong antipathy to both of them.
That means Romney's toast, in my view. As the weakest candidates leave the field, they will go to whoever Tea Party people like at that moment. The survivor amongst that group wins.