For Democrats, the warning shots are coming thick and fast.

“More than half of Americans don’t think Donald Trump is fit to serve as president, yet he has a clear path to winning reelection,” Doug Sosnik, who served as President Bill Clinton’s political director, wrote in the Washington Post last week. “Are Democrats Headed for a McGovern Redux?” Alan Greenblatt asked in Politico on Oct. 9. On the same day, a New York Magazine headline declared: “No One Should Rule Out a Trump Re-election in 2020.”

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Nathaniel Persily, a professor of law and political science at Stanford, makes the point succinctly, focusing on the importance of candidate recruitment: “How can the party nominate someone, or be led by someone, like Bill Clinton, rather than Hillary Clinton?”