If Hillary or Barack had won decisively, then the calls to drop out would be understood by all. But neither has. Barack is in the lead and has the advantage. But at this point in time, neither his lead nor his advantage are decisive.
It says the Kenndys did give $100,000 to help bring Kenyan students here but in 1960, after Obama's father came to the United States. What year does Snopes say the donation occurred? They don't. They say "a few years before being elected President" and the uncredited passage they site states that the Kennedys donated without giving a specific year. So how exactly does Snopes "defeat" the Washington Post?
Interesting that you would use that particular quote from the speech. Barack's campaign has done all those things: bred division, conflict, and cynicism. If he's going to say we, as a country, can say "not this time," he needs to start with himself and his campaign.