The following statements are my opinions and theories:
Huckabee does not like Romney for one reason and one reason only. Mormonism. Huckabee is a conservative Christian and sees mormonism (correctly, I might add) as heresy. Huckabee does not trust a mormon as the leader of this country. Huckabee believes that a Romney administration will be packed with other mormons and sees this as a big problem. Huckabee torpedoed Romney's 2008 primary run for this reason and this reason alone. Nothing else explains his behavior in 2008.
That said, I do not believe that Huckabee is supporting Akin for the purpose of yet again torpedoing Romney. I think that Huckabee saw himself (correctly) as largely unable to prevent Romney from gaining the nomination this time around and has therefore dropped his opposition. I think Huckabee's support of Akin is rooted in his Christian faith, his pro-life principles and Huckabee's self identification as some kind of a power broker for conservative Christian voters and it is nothing more complicated than that.
Here is a quote from the Huckabee wikipedia page:
Huckabee has stated, "Politics are totally directed by worldview. That's why when people say, 'We ought to separate politics from religion,' I say to separate the two is absolutely impossible".
You may, of course, draw your own conclusions. These are mine.
EDIT:
Politico has an in-depth report about the conference call Friday afternoon between former Arkansas Gov. Mike Huckabee and "hundreds of Southern Baptists" in which he invoked Old Testament imagery to explain the task facing Republican U.S. Rep. Todd Akin and his supporters.
In the call, he railed against the pressure being brought to bear on Akin to quit Missouri's U.S. Senate race and compared Republican establishment to "union goons" in their treatment of vendors and consultants. Huckabee said he was personally pressured after his decision to support Akin and his decision to stay in the race against Democratic incumbent U.S. Sen. Claire McCaskill.
The issue was portrayed as a test of faith when Huckabee said this, Politico reported:
"'This could be a Mount Carmel moment,' said the former Arkansas governor, referring to the holy battle between Elijah and the prophets of Baal in the book of Kings. 'You know, you bring your gods. We’ll bring ours. We’ll see whose God answers the prayers and brings fire from heaven. That’s kind of where I’m praying: that there will be fire from heaven, and we’ll see it clearly, and everyone else will to.'"
LINKMay God prove him correct. But...God has also taken down
other prominent people who use His name to demagogue and promote their own agendas.