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.
Huck would be completely radioactive in 2/3's of the country but he would be a great cultural fit in the other 1/3 especially the Jeffersonian upper southern states like Missouri , Arkansas , WV etc.
He is actually a nice likeable guy that has some moderate even liberal economic policies. He could appeal to some working class blue collar whites that were turned off by Mr Plutocrat 47 % in 2012. Although he would get slaughtered in the Northeast and West Coast , Hillary might break 70 % in NY and MA.