The VP question is frustrating me, and I don't think Barack is giving good enough answers.
Here's what I'd say:
" Making hints about a VP right now, before the nomination is decided, can wind up being insincere to voters. I mean, you never know what will happen when the person actually gets the nomination. What if they suggest they'll take someone for their VP, and voters vote for them expecting this, but then after the nomination, they change their mind for some reason? It would be a disappointment for the voters. So, I don't think VP nods should be hinted at during the nomination process. If you want to see someone on the ticket, the best guarantee you can have is by voting for them."
Right now, B's responses are getting mixed response. When he emphasizes that he's running for President, not VP, some take it as immaturity: no I'm not going to be her VP. But he has a point: it's premature, we should focus on the presidency. He just needs to make his response clearer. You can't argue with the response that it's unwise to make promises you might not be able to keep and can end up being an insincere way of influencing voters.
I still see the Bill Clinton veep statements on front pages and I cringe. It's cunning. McCain refused to do this even when he knew he was headed to nom. Obama refuses to do this. It's low of the Clintons to do this.