Bill Kristol, speaking to Bloomberg Politics:
The real last chance here is with Mitt Romney, who has said "no" but who I think is thinking seriously about it. He is a very serious person, he really knows that Trump should not be president of the United States. He strongly believes that Hillary Clinton should not be president of the United States…. I think he thinks someone should [run as a third-party candidate]. And I think that he thinks that maybe he is the right person to do it. He has the national stature and name ID, access to resources.
Notes Bloomberg: "Reached via e-mail, a Romney spokesperson declined to comment on Kristol's assertion."
Romney's no comment is more interesting by far than Kristol's comment.