Bill and Hillary had that arrangement all along. Barak and Michelle?
I worked at a major university for a few years, and it was a well known "secret" that a lot of the high-tower administration's marriages were scams. They would get married to look normal, so their careers/ambitions wouldn't be harmed. I'm certain that also applies to politicians and their spouses, or any elite group.
Barak and Michele?
Yes, they were both allowed to date any man they wanted!