A Tom Steyer Debate Spot Is in Limbo. His Money Is Poised to Upend 2020 Anyway.

He has spent millions pressing for the impeachment of President Trump in television ads that promoted himself and his group Need to Impeach, while building up an eight-million-strong email list he can now pay to access (his campaign must technically rent the list, but that is little more than an accounting concern). And he constructed an environmental advocacy group, NextGen America, with chapters across the nation.

“He’s built an infrastructure that can be turned into working for a presidential campaign,” said Kevin Mack, chief strategist for Need to Impeach.

More than most first-time candidates, Mr. Steyer has some experience in retail-level politicking, having fielded questions at town hall events around the country held by Need to Impeach. Still, he can be stilted.

At the state fair, Mr. Steyer was pushed by an Iowa farmer about how a $15-an-hour minimum wage would work in rural areas. “I respect you’ve built a 37-million — billion — whatever it is,” the farmer, Kyle Gilchrist, said. “I’m a poor man from Van Buren County.” Mr. Gilchrist said he still baled hay himself. The billionaire lifted the farmer’s T-shirt sleeve to inspect his biceps, nodding in approval.

Mr. Steyer is not a self-funded politician in the centrist mold of former Mayor Michael R. Bloomberg. In some ways, Mr. Steyer is a liberal occupying the same structural reform space as the progressive leaders in the polls, Ms. Warren and Mr. Sanders. He has embraced decriminalizing the border, expanding the Supreme Court and, as a private citizen, proposed a “wealth tax” on assets of the super rich last fall, before Ms. Warren did.

“Virtually everybody else in this race, including those two senators, comes from D.C., is part of the establishment,” Mr. Steyer said. “So if you think the problem is broken government, which is what I think, if you think that the corporations have bought the government, who do you think is going to reform it? Do you think it’s going to be someone from the grass roots, from the outside, who’s done it for 10 years? Or do you think it’s going to be someone from D.C.? It’s a fair question.”

If the idea of a wealthy mogul running as an unbought outsider against a rigged system and the political establishment sounds familiar, that is no accident.