Backstage, Senator Kamala Harris smiled and exhaled, appearing both excited and relieved. Harris had just successfully navigated 12 minutes of being interviewed by Stephen Colbert, an experience that mixes goofy comedy with sudden downdrafts of pointed questioning, all in front of a live audience of 400 and a half-dozen cameras that will beam the conversation to millions more Late Show viewers. She had been bracingly blunt in declaring that Paul Manafort is guilty of conspiring with the Russians to interfere with the 2016 election (“What more do we need to know?”) and had issued a perhaps overly optimistic guarantee about how the government shutdown will end (“It does not end with a wall”). Harris had managed to work in her somewhat clunky catchphrase (“If it’s worth fighting for, it’s a fight worth having”) and to tease the official announcement of her presidential run (“I might!”). Judging by the raucous cheers of the studio crowd, Harris already had a few believers. But immediately afterward, the senator seemed most proud of having gotten a laugh out of Colbert, a moment that happened after the TV cameras shut down.

Harris was visiting Colbert ostensibly as part of a multi-city tour to promote her two new books—one for grown-up voters and one for future voters (children)—but clearly to promote her forthcoming bid for the 2020 Democratic nomination. It’s all of a piece, carefully assembled over the past year. The title of Harris’s memoir, The Truths We Hold, is not an accident; it fits snugly into the frame her camp has devised for the contest ahead. Harris and her advisers believe that the fight to defeat President Donald Trump will bear parallels to the 1976 presidential campaign—even without Trump emulating Richard Nixon by resigning and being replaced by a Midwestern vice president. Harris’s team sees a similar context: a Republican incumbent from a party with a fresh history of corruption and pervasive untruth being challenged by a Democrat who is a relative Washington outsider promising to restore honesty to public life. In the 2020 sequel, Harris plays a tougher, gender-ceiling-breaking version of Jimmy Carter.

“What we’ve lost recently, but must remember and fight for, is the nobility of public service,” Harris told Colbert. “We hold these positions as a public trust, and there is some assumption that the American public rightly makes, that when we have this power we will use it in the best interests of the people, not in the best interests of ourselves. . . . Leadership, especially when we’re talking about the highest office in the land, has to be focused on what is the right thing to do, and in defense of the ideals that were part of the founding of our country. A lot of people in our country are rightly feeling a great deal of distrust in their government and its leaders and institutions. And we need leadership that speaks truth as a foundation for building trust. And right now we’re not getting that.”

Minutes later, in the narrow backstage hallways of the Ed Sullivan Theater, Harris described what happened right after Colbert shook her hand and cut to a final commercial break. She had asked him to flip to the final page of Superheroes Are Everywhere, Harris’s new book for kids; Colbert obliged, and burst into a laugh. “When we were doing the book,” Harris tells me, “I told the designers I wanted the last page to be a mirror, so kids can look in it, and the text on the page says, ‘And the superhero is you!’ Stephen looked at it and started laughing.” Told that she had probably made some political news during her interview with Colbert, Harris nods. “It’s an interesting time we’re living in, isn’t it?” she says, the sobriety quickly returning to her eyes. “It’s actually a scary time.”

Then she does something decidedly human for a professional politician—she shows an awareness of the other people in the room, introducing me to her sister, Maya, a lawyer and criminal-justice advocate. Bradley Whitford, another guest on tonight’s Colbert show, walks silently by—the television West Wing past crossing paths with a possible real-world West Wing future. The Harris sisters head out the door to West 53rd Street and to dinner. Climbing into the back of a huge black S.U.V., Harris is really beginning a trip down a much longer road.

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