If the pattern of the campaign so far holds, I would expect to see Obama give a skillful defense of his bitter/cling goof, possibly accompanied by a ham-fisted effort by Hillary to advance the story. (Remember her painful "change you can Xerox" debate line?)
Otherwise, I'm not sure what the candidates have left to tell us or anyone else. Here's a thought: If what is really still driving Hillary is the idea that she's more electable, and that's what she and her coterie are telling superdelegates, why not just lay the damn thing out? If it's so true, and you really believe it, just explain it straight up, rather than nodding and winking and hinting. Drop the charade, make your best arguments. Name specific swing states. Have a real debate, not a weird battle of cutesy soundbites.
I won't hold my breath.