As someone who has been critical of Huckabee in the past, let me say I admire his courage here -- and I also think this is smart strategy.
While many of his potential 2012 opponents all have PACs -- HuckPac has been especially good at coming out early for conservatives in tough primary campaigns. What is more, he seems to be identifying conservative candidates who -- whether they win or lose -- have a strong and loyal base in their state.
Let's suppose Rubio loses. He will still be a conservative rock star who can command crowds in Florida. And while every establishment Republican is begging Charlie Crist for support (which he will withhold until he already knows who will win so he can once again be a kingmaker), whom do you think Rubio will support in the Florida primary?
I've got one hint for you: His name is Huckabee. Why? Because candidates who are in Rubio's shoes are very appreciative of support. Anyone can send you a check and endorse you after you win the nomination -- but the early support is what matters and what is appreciated.