Washington (CNN) Remember that episode of "Seinfeld" where George Costanza realizes that once he tells a successful joke, he should immediately declare victory and leave the premises? The plan succeeds beyond his wildest dreams as his boss finds himself always wanting more George -- to the point that he fires everyone on the project because he thinks George can handle it all himself.

That's kind of what -- I suspect -- Nikki Haley did on Tuesday when she shocked the political world (no matter what President Donald Trump said) by announcing her resignation. (I also wrote about a series of theories as to why she decided to leave, specifically, right now .)

Haley will have spent, roughly, two years in the Trump administration by the time she officially leaves at the end of the year. She will depart as a Trump favorite -- as he made clear when he held a quasi press conference with Haley on Tuesday to announce her departure. He praised Haley's service and said that if she ever wanted to return to the administration, she could have whatever position she liked.

So, she's checked the "OK with Trump" box. And she's done so, somewhat, amazingly, without turning off Democrats (and non-Trump Republicans). In a Quinnipiac University poll conducted in late April , more than six in 10 people approved of the way Haley was doing her job. That number included, again somewhat remarkably, 75% of Republicans AND 55% of Democrats.

The truth is, given Trump's volatility as it relates to his advisers and the tremendous tribalism of our politics, it's hard to see how things could get much better than they are right now for Haley. And so, like Costanza, she went out on a high note.

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