Editor’s note: This post has been updated with a response from Donald Trump.

Hmm…

Any guesses? Could it be John Kasich:

Or Mitt Romney for round 3:

Maybe he means the Libertarian ticket of Gary Johnson and Bill Weld:

Or given Kristol’s much-mocked prognostication abilities, game over on a 3rd-party challenge to Trump and Clinton:

Well, whoever it is, many are pretty sure that a 3rd-party candidate has no shot:

We. Shall. See.

Update. Trump responds:

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