The #Pantsuitpower flashmob at New York’s Union Square. Photo by Laura Crozier.

It came together in about a week. First, the idea for a punchy, uplifting dance video that would tell a story about diversity, difference and communal support. Then, 170 dancers, a few hours of rehearsals–and pantsuits. Lots of pantsuits.

The result: the #Pantsuitpower Flashmob for Hillary dance video, performed at New York’s Union Square. It’s gotten nearly 2 million views on Facebook in a matter of days.

The video, accompanied by Justin Timberlake’s contagiously boppy disco-pop song “Can’t Stop the Feeling,” was posted on Facebook and Vimeo this week by Humanity for Hillary, a social media campaign aimed at artists, in support of Democratic presidential candidate Hillary Clinton.

“I wanted to bring some kind of humanity to her campaign, because I think humanity and love and humor tend to get lost when we’re in the heat of all of this,” says Celia Rowlson-Hall, 32, a New York-based choreographer who’s worked on HBO’s “Girls” and other TV shows and music videos. She and her Washington, D.C.-based friend, hiphop choreographer Crishon Landers, created the pantsuit dance, and Rowlson-Hall directed the video with her partner, Mia Lidofsky, an independent film producer. The couple met on the set of “Girls.”

“We just felt the need to do something,” Rowlson-Hall says. “We thought, how can we creatively impact this election? So we made the video.”

There’s nothing like dance to convey enthusiasm and energy, so it’s a natural political tool. The fact that it’s rarely used to rally voters–and even more rarely used so well–is what makes this video feel so fresh. That, and the clarity of the choreography, the invigorating spirit and skill of the video’s massive chorus line, and the catchy tune.

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A graduate of North Carolina School of the Arts, Rowlson-Hall has worked in the New York dance scene for the past decade, first performing with a couple of troupes, and more recently choreographing for stage, film and television. She made her feature-film directorial debut with “Ma,” writing the wordless script, choreographing it and starring in it; it became a favorite of the 2015 American Film Institute Festival. She and Landers choreographed the flashmob scene in about four hours, she says, using simple, clear moves drawn from hiphop, ballet and modern dance. Each bears a message: Raised fists signify #BlackLivesMatter, arms and faces tilted to the sky hint at solar energy, circling hips symbolize reproductive rights. In the quietest and most emotional moment, dancers take a knee to evoke San Francisco 49ers quarterback Colin Kaepernick’s national anthem protest against police brutality. Others stand with a hand on their hearts.

“This is our right as a democracy to protest or honor the flag as we see fit,” says Rowlson-Hall. 

She put the word out on Instagram and Facebook seeking dancers. She videotaped herself dancing the steps, and texted it to the dancers who’d replied. Many are professionals. A few came from Broadway’s “Fiddler on the Roof” and the Martha Graham Dance Company. Some came from as far away as Toronto. Assorted “dance enthusiasts” joined in–dentists, other artists and little girls fresh from soccer practice. They had a couple days to learn the moves on their own, then they met in small groups for one-hour sessions with the choreographers. That’s when they were also fitted for their pantsuits, an homage to Clinton’s go-to workwear. A few suits were donated by Topshop. Stylists scoured thrift stores for the rest.

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Near the end you can glimpse the slender, short-haired Rowlson-Hall grooving in a pinstriped suit, her T-shirt emblazoned with “The Future is Female.”

For all the ebullient energy of the dancing, the video also produced some headaches. The directors didn’t have a permit to use Union Square for their shoot.

Designer Nina McLemore knows how to dress with attitude, which is why presidential candidate Hillary Clinton, Senator Elizabeth Warren and some of the nation's most powerful women look to her for fashion advice. (Erin Patrick O'Connor/The Washington Post)

“We were terrified we’d get shut down by the cops,” says Lidofsky. They also feared pushback from Timberlake. They reached out to his manager about using his song, Lidofsky adds, but with no reply they plowed ahead, hoping Timberlake wouldn’t mind. (No word from him yet.)

The only time the whole group rehearsed together was 20 minutes before the taping last Sunday morning, Oct 2.

“The dancers came knowing the choreography to a T. I’ve never seen dancers work like that,” says Rowlson-Hall. “It was a whirlwind.”

Clinton has some appreciation for dance: Her daughter, Chelsea, was a Washington School of Ballet student during Bill Clinton’s presidency. So far, however, Hillary Clinton has been silent about the pantsuit dance.

“But we’re refreshing our email every single minute,” Lidofsky says with a laugh. “We really hope she saw this, and felt the love.”