Pleasanton, Calif.

Can Donald Trump possibly win the presidency? For months Scott Adams was asking if Mr. Trump could possibly lose. Mr. Adams now believes the answer to the latter question is yes—although, unlike most professional pundits, he hasn’t written off the Republican nominee. And while he speculates Mr. Trump may have a tendency toward “self-sabotage,” he attributes Hillary Clinton’s strong performance in recent polls mostly to her campaign’s improvements rather than to Mr. Trump’s missteps.

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