Delegates are now free agents, by party rules, but likely it will be seen a better chance of winning if they accept Joe's endorsement of Harris (especially given her sterling resume) rather than waste time on all the horsetrading and pyrotechnics of an open convention. If they still do the early pre-convention nomination balloting, they can give Kamala and Veep a couple extra weeks.
I'm hearing all kinds of weird buzz. One is a Unity ticket, e.g. Harris-Cheney or Harris-Kinzinger. While such a hypothetical fistful of bipartisanship could be interesting and motivating to some Log Cabin Republicans and Indies, I doubt it would happen. More likely, a strong governor as a VP, like Beshear, Newsom, Shapiro or Whitmer. Or a Mindbending Number of Firsts ticket, Harris-Buttigieg.
I want to be the first to point out that a Harris Beshear pairing could be called (cough) the Barber Ticket. 🙄