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Robert De Niro, Alec Baldwin, Cher, Mark Ruffalo, Rosie Perez, Sally Field, and other celebrities joined thousands of protesters and New York Mayor Bill de Blasio Thursday night at an anti-Donald Trump rally organized by Michael Moore outside of the Trump International Hotel and Tower in Manhattan.

The New York Police Department estimates that 20,000 to 25,000 people were at the "We Stand United" rally, Deadline reports. "We Americans, we New Yorkers, we patriots will stand united for our rights and the rights of our fellow citizens," De Niro told the crowd, while Cher said: "The only thing that can save us is you. Nothing happened to stop Vietnam until we got into the streets. The power of the people is bigger than the a—holes who are there in Washington."