Obama supporters (I am one) need to acknowledge that the Clinton campaign has succeeded in its objective to damage Obama's candidiacy to the point that a political stalemate is likely.
The race card is on the table; face up. It ain't going back in the deck and it's having the predicted negative effect on Obama. Actually, it was a brilliant, if nefarious, strategy by the Clinton campaign as they had so little support among AA voters in the primaries that it couldn't hurt them in that demographic, only help with white working class and ethnic voters (GE effect is a different story; see below).
Now that Obama is potentially damaged goods to a significant portion of the Dem target voters and Clinton has deeply alienated young and AA voters, the prosepcts for either in the GE is diminished.
IMHO, only Obama has the stature and leadership to make a move to heal the racial divide within the Dem party ... by offering the VP slot to Clinton. This willingness to reach out to and implicitly forgive the perceived race-baiter would put meat on the bones of Obama's soaring unity rhetoric.
I believe most Obama and Clinton supporters would accept this as fair and even smart in the current context of a closely split and increasingly divisive race. The harsh rhetoric and tactics would soon be forgotten as the prospect of a sweeping GE victory would heal most, if not all, wounds.
Yes, it would take courage and wisdom for Barack to do this but I think (or at least, hope) he can.
What about Hillary? Could she settle for "second place"? I think so. First, she would still make history as the 1st female VP. Second, at age 68, she would not be too old to run for Pres. in 2016 (cf. Reagan, Dole and McCain), with the presumed add'l advantage of being a sitting VP. Finally, I think she and he advisors realize that if she were to wrest the nomination from Obama, she would inherit a deeply fractured party, resulting in likely defeat in the GE and the end of her Presidential ambitions.
Why not Clinton/Obama, you ask. Symbolism matters here. IMO, asking the black man who is likely to be the leader in both pledged delaates and total votes to settle for 2nd place would not heal the division in the party, although if Barack were to sincerely offer it, who knows?