I have never thought he is ignorant, just a predictable product of his military background and upbringing (his daddy's daddy, his time as a Vietnam POW, The Surge (soon to be a Hollywood Musical).
That actually makes him quite authentically himself to voters, in the same way Clinton, despite her "high negatives" on personality polling, is also authentically herself: the woman who sat on the lap of the man seated on the throne of power, is authentically herself.
The only candidate of the three who isn't authentically themself is Obama.
One can't connect who is to his policy stands. That will work against him in the general election, especially when the other half of the voters wake up and see the Wright videos, which haven't hurt him among Dems.
It will definitely hurt Obama among general election voters, just as soon as they start paying attention to the race, sometime in October of this year.