Yet she also slid seamlessly into the surrogate role for Mr. Booker at a half-dozen campaign events in Iowa over the weekend. She has braved the post-debate spin room in the past, and often sees her own selfie lines form on the trail.

“He’s the only candidate on the stage at the debate talking about, ‘We need to address the child poverty system,’” she said as a gaggle of women formed around her after taking selfies with her in Davenport, echoing the candidate’s message that his voice and platform need to be on the December debate stage.

Ms. Dawson, of course, is no stranger to politics. Growing up in New York City, she helped her mother campaign and canvass for local politicians, “licking stamps and envelopes and pushing for local city councilmen and women.” She was an active surrogate for Mr. Sanders during the 2016 primary. She co-founded Voto Latino, a nonprofit voting rights organization, 15 years ago; is active in the Lower Eastside Girls Club of New York; and is on the board of V-Day, a global nonprofit to combat violence against women.

The thought of running for office herself has occasionally crossed her mind.

“I’ve had definitely a lot of friends who called me Senator Dawson over the years, which cracks me up,” she said. “I’ve always been sort of curious about it.”

A goal of her time on the Iowa campaign trail, however, would also meet a need for the Booker campaign. Though the team has taken an R.V. on the road in both Iowa and New Hampshire, no one on the campaign currently has much experience driving the bigger vehicles.

But Ms. Dawson does.

“I would drive an R.V. in a heartbeat,” she said with a laugh.

Both Mr. Booker and Ms. Dawson recognize that their time together on the trail may be limited — Mr. Booker jokingly asked the crowd in Davenport to invite Ms. Dawson to be a surrogate for him if he has to be in Washington for an impeachment trial — but Ms. Dawson said she felt the same budding energy of a late upswing that Mr. Booker said he saw around the state.