Lena Dunham, Amy Schumer, Whoopi Goldberg and other celebrities are joining forces to protest Supreme Court nominee Brett Kavanaugh on Thursday.

The #CANCELKAVANAUGH protest was held Thursday outside the E. Barrett Prettyman Federal Courthouse a few blocks from the U.S. Capitol.

Dunham, the creator of "Girls," seemed pleased with the turnout: "So many women I love are in DC today," she tweeted. "They represent hundreds, thousands, & millions of other women. At this point, opposing Kavanaugh is not about a political party ... it’s about ensuring that women-people-of every political party are safe."

She added, "Trauma is a silent killer. I pray – truly, yes, have been praying – that our senators on both sides of the aisle recognize their own moral imperative to believe and protect survivors."

Schumer, who posted a photo of herself on the train from New York to DC, posted a couple of signs to her account Thursday ahead of the protest.

"Did you know women aren't mentioned in our Constitution?" one asked. "We aren't protected." Another quoted a passage from "To Kill a Mockingbird": "No matter how the vote goes, I give you Atticus, 'I want you to know, Jen, that courage is not a man with a gun in his hand. Courage is when you know you're licked but you begin anyway and you see it through. You often don't win. But sometimes you do.'"

John Legend, who was reportedly planning to attend, tweeted Thursday that he would not.

"I support this protest, but it has been misreported that I will be there," he wrote in a tweet. "I never was able to be there. #CancelKavanaugh"

Other musicians, actors and activists scheduled to participate included Erykah Badu, Maggie Gyllenhaal and husband Peter Sarsgaard, Norman Lear and Michael Stipe, among others. Don't look for them all to be in D.C., though. According to the site, "We will not all be in DC but ask you to walk out wherever you are."

"We anticipate a vote on the Senate floor to confirm Brett Kavanaugh as early as Friday," the group's organizer, Party Majority PAC, wrote on the event's website. "It is critical we make our voices heard on the ground in Washington on Thursday."

The website continues: "If there was ever a moment when the voice of the people can come together in concert to change the fate of our nation, this is it. Arm in arm, organized and ready, every child, woman, and man, must take to the streets to protest this nomination."

Organizers urged participants to join the demonstration in Washington or locally and phone key senators, such as Maine Sen. Susan Collins and Arizona Sen. Jeff Flake.

Related: Alyssa Milano: It was 'difficult' to attend Kavanaugh hearing amid phone fiasco, outfit shaming

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