Republicans need a viable leader as the nominee. Romney or Huckabee won't do it.
Perhaps Democrat voters will not abandon Obama, but I think the odds are increasing that Democrat elites may be searching for a way to throw him under the bus.
It is increasingly clear to them that this guy is a dangerous incompetent who risks taking what remains of their party completely over the cliff in the next election cycle. If they can figure a way to do it while still hanging on to the black vote look for an attempt at a palace coup here.