Huckabee's biggest problem in 2008 was a lack of financial support. So Adelson's support could obviously be big.
Otherwise, he's become a weaker candidate since '08. His last general election campaign was in 2002 (where his Democratic opponent got about 47 percent), and he's kinda been in a bubble communicating mainly with friendly crowds (both in terms of primary support and GE support) not quite understanding certain social changes. He would be a top-tier contender for the nomination, but one with a glass jaw.
Huckabee would lose 40 states vs hillary clinton. There is not a single person who did not vote for Romney, that would vote for him. He appeals to no one.
If you're a libertarian, he's a nightmare candidate: socially conservative, but fiscally moderate (if not liberal.) He might appeal to voters who think the problem with government handouts is that they're not getting their fair share. There are plenty of those guys in Ohio and Pennsylvania.
