WASHINGTON – There is one clear area where President Donald Trump has had a unifying effect on Capitol Hill: the color Democratic women wear to joint sessions of Congress.

The chairwoman of the Democratic Women’s Working Group, Florida Rep. Lois Frankel, encouraged members to wear white to this year's State of the Union address as a shoutout to the voters who handed Democrats a majority in the House in the midterm elections and a reminder that they plan to make women's economic security a priority.

The color choice is also meant to honor the women's suffrage movement that led to the ratification of the 19th Amendment in 1920.

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"By wearing suffragette white to #SOTU2019 tmrw we’re sending a message to everyone that voted for @HouseDemocrats & delivered us the majority that we're working #ForThePeople, promoting the economic security of women & their families!" Frankel said in a tweet Monday.

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In a show of unity, hours before the State of the Union scores of Democratic women gathered on the spiral steps of the Capitol Visitors Center to take pictures, hold hands and pin on “ERA” buttons.

“Girls Rock!’’ yelled Michigan Rep. Brenda Lawrence, a member of the Democratic Women’s Working Group.

One by one, more women, including Speaker of the House Nancy Pelosi, wearing white in honor of the women’s suffrage movement joined others on the steps.

Minutes before the photo op, the Democratic Women’s Working Group held a press conference highlighting some of the challenges women continue to face, including pay inequity, high rates of poverty and lack of access to quality health care.

“Tonight when President Trump gives his State of the Union and when he looks at the Democratic side of the House he will see a wave of suffragette white as Democrats promote a crucial piece of our “For the People” agenda,’’ Frankel said.

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It’s not the first time Democratic women have worn white at a joint session of Congress. But Rep. Nita Lowey, D-N.Y., called it “thrilling” to be among a record number of women serving this Congress.

“This is really extraordinary,” said Lowey, who is serving her 15thterm. “We intend to use women power to set the agenda and to make sure that we are fighting for women and families and the future.”

The women were not alone. A few male members of Congress stood nearby, including Majority Leader Steny Hoyer of Maryland.

And Rep. Dean Phillips, D-Minnesota, even sported a white tuxedo jacket. He said he went everywhere Monday looking for a white jacket.

At one point, Rep Alexandria Ocasio-Cortez, D-N.Y., pinned a green ERA button on Phillip’s jacket and gave him a high-five.

“I support all my brothers and sisters, but my sisters have really taken this place up a notch and brought some energy and inspiration,” Phillips said. “I’m celebrating and I want to join them. My mom, when I was little boy, had one of these pins and I’m honoring her’’ too.

Phillips said his move was well received by his female colleagues.

“I think I earned a little bit more love,’’ he joked.

Democratic women also wore white to Trump's first speech before a joint session of Congress in 2017, about a month after his inauguration and the massive Women's March on Washington. At the time, Frankel said they wore white "to unite against any attempts by the Trump administration to roll back the incredible progress women have made in the last century."

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Hillary Clinton also wore white when she accepted the nomination for president at the 2016 Democratic National Convention in honor of the women's suffrage movement. And Geraldine Ferraro wore white when she accepted the nomination to become the first female candidate for vice president for a major American political party at the 1984 Democratic convention.

Last year, Frankel's working group encouraged members of Congress to wear black to Trump's first State of the Union address to express solidarity with the #MeToo movement. Rep. Jackie Speier, D-Calif., also said it was meant to send a message to Trump, who himself has been accused of sexual harassment.

"The last couple years we were basically reflecting back to Trump," Frankel told Roll Call. She said this year it was a "much more positive" message, "emphasizing economic security for women and their families."

One big change this year: new House Speaker Nancy Pelosi, D-Calif., will be sitting behind the president as he delivers his address. And Pelosi – the woman who recently went toe-to-toe with Trump in the government showdown – will likely be wearing white.