The word on the street is that the Obama campaign and New York Mayor Mike Bloomberg have already met and devised an incredible plan if Clinton wins the nominee. Mayor Bloomberg would give nearly $1 billion to Obama's campaign after which Obama would bolt from the Democratic Party and run as an Independent candidate with king-maker Bloomberg as his running mate. The Obama campaign realizes that Obama is too new at this game and doesn't have the political weight of the Clintons to bring in the true heavy-hitters of the party's hierarchy. So, according to sources it was Bloomberg himself who suggested this cunning strategy. It's mind boggling that the Clintons are willing to destroy the entire Democratic Party, and potentially in the process lose the White House and seats in Congress, for their own selfish thirst for power and glory.
That's a good rumor directed at the Democratic power brokers: you could lose everything if you support Hillary in her attempt to steal the nomination. It's just barely plausible enough that Clinton supporters might have to stop short of subverting the will of the voters. Personally, I don't think Bloomberg would want to run as a VP so the whole idea sounds preposterous. But it shows that Obama can play tough with the Clinton machine.