Considering that she was in her twenties, and McCain in his forties when they met, that was a smart move on her part in a time where pre-nups were uncommon. I guess she saw what happened to Carol and decided her money was great glue to hold a marriage together.
Or maybe it was McCain's sugar daddy-in-law who had the smarts and set up the arrangement.
I remember when McCain got all snarky about Romney's wealth--Romney who had earned his fortune, instead of marrying it like McCain and Kerry. I didn't know at that time just how rich Cindy is.
Actually, as much as I like Governor Romney, he came from wealth. George Romney did very well for himself.