"The public WANTS to like him...".
That ship sailed when he hit 38%- the reality is, people are (for now at least) siding with the familiar- failures, be damned- because nobody has really stepped up to the plate and offered a compelling, competing vision for the future and really gone after Obama's disastrous policies (yet)- although that's natural during primaries when the focus is other opponents.
"... whoever we nominate better be capable of running an excellent campaign.
Very true.
I am more than sure that the biggest problem is that there are capable candidates out there, they just aren’t able to really market themselves effectively. The best brains in the room are often the least able to effectively advertise themsleves. Look at how Steve Wozniak was; he was briliant, but Steve Jobs was the best at marketing and getting the message across.