Celebvocates! Using their atmosphere-altering star power to try to effect change in our nation’s capital. An occasional look at the show-biz folks who come to D.C. to push a favored cause. Wednesday’s visitor:  Christina Aguilera.

Christina Aguilera and Hillary Clinton during the photo-op portion of the day. (Paul J. Richards/ AFP/Getty Images)

Cause: U.N. World Food Program

Bona fides: Four Grammys, judge/coach from team-singing competition show “The Voice,” longtime WFP booster.

Backup: Hillary Clinton; Yum Brands CEO David Novak; USAID Administrator Rajiv Shah; veteran journalist and GWU professor Frank Sesno.

What she wants: For you to donate 19 cents a day to help feed a starving child.

How she looked: Kinda sexy, but not inappropriately so. Deep burgundy dress revealing a bit of decolletage. Nude Louboutins with a silver toe. Braided bun showing off her pink and purple streaks.

How she sounded: Decidedly less dirrty than she used to. Touted her mom credentials — how having a 4-year-old has changed her perspective on the hunger crisis, reports our colleague Megan Buerger. “Being a mother . . . it’s a selfless act,” she said. “But why not these kids? Why not give them the same opportunities?”

Personal anecdote: On a recent trip to Guatemala, she visited factories operated by women with the assistance of the World Food Program. “It was amazing to see that women are building their own businesses because it really starts with that, a foundation to build from and pass onto their children.”

Distraction: So many plugs for Yum Brands (the conglomerate behind Taco Bell, KFC and Pizza Hut, whose World Hunger Relief has raised millions for WFP).

Obligatory pop-culture reference from Secretary Clinton: “If I could sing, Christina, I would want to be on your team. But since I can’t, I’m glad you’re on this team.”

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