To paraphrase the Godfather, that was a matter of "keeping your friends close but your enemies closer."
If she didn't end up on BO's team, she would have knocked him as a talking head for four years. And he'd be looking at an uphill battle this week. She wouldn't have run against him. She'd never tear the party apart a la Teddy Kennedy in 1980. But she would have made his re-election an uphill climb this year.
I still don't believe there's any love lost there. But they're both smart enough to realize that other old proverb: The enemy of my enemy is my friend

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