Standing out will require one nonnegotiable quality: the vividness to loosen Trump’s stranglehold on the media. To that end, any serious challenger has to figure out how to tell his or her story in a riveting way.

“High emotion” was how Naomi Burton described what a candidate should reach for. She and Nick Hayes run the Detroit firm Means of Production, which helped with the viral biographical video at the center of Alexandria Ocasio-Cortez’s stunning rise. Hayes told me that candidates should be wary of relying on “traditional commercials, which people are bombarded with on a daily basis.”

Trump tweets to bold if bilious effect. His opponent must also bend social media to his or her will. Many Democratic politicians have been trying to do that, with varying success. O’Rourke’s defense of football players who kneel during the national anthem went as viral as imaginable, and his live streaming of everyday minutiae on Facebook has been the perfect complement to his folksy, hyper-accessible brand. But Senator Cory Booker’s self-described Spartacus moment during the Brett Kavanaugh hearings didn’t quite pan out — his rebellion was more transparently stagy and less audacious than advertised.

There’s no exaggerating the hell of jostling for space at the media trough where Trump gorges to the point of bursting. He has shamelessness on his side. Look at last Tuesday: His claim that he might end birthright citizenship through an executive order became the main news story, even though he can do no such thing, almost certainly knows that and was engaged in a political stunt meant to energize the base for the midterms. Some morsels are just too delicious for journalists and pundits not to sup on.

So there’s pressure on a Democratic challenger not just to communicate memorably but to say memorable things — i.e., new ones.

“Candidacies need to have a level of originality and ambition,” said Pete Buttigieg, the young mayor of South Bend, Ind., and a rising star in the Democratic Party. He stressed the policy side of this and possible discussions about “whether guaranteed income is now right — a more novel idea like that. I think you’re going to hear more people talking about constitutional amendments in a way that we really haven’t since the E.R.A.” Those amendments might touch on the Electoral College, on campaign financing, on voting rights. His point — a vital one — was that mere tinkering with the tax code or amorphous job-training proposals are yawners for duller times. They pale beside a border wall and a Muslim ban.