More likely for it to be Michelle. I believe she is waiting in the wings to swoop in and “save” the party when it dissolves into chaos at the convention.
That’s my scenario for Hellary!
I could see her offering the VP slot to Michelle.
But has this scenario ever happened in the modern era? Every nominee in at least the past 50 years has had to slog their way through the primaries and undergo the entire campaign before being nominated. I can't remember the last time somebody in either party just "swooped in" at the convention and took the nomination without having to go through a single debate or a primary.
So as far as I'm concerned, all this talk about Michelle Obama being anointed at the convention to the acclaim of all is just a bunch of empty talk.