Madonna played a surprise Hillary Clinton concert at Washington Square Park Monday night.

Madonna played a surprise Hillary Clinton concert at Washington Square Park Monday night.

(MATT ROURKE/AP)

The Queen of Pop made a surprise appearance at Washington Square Park Monday night and told voters to “Express Yourself” on Election Day.

The impromptu concert drew a large crowd despite cold temperatures and little advance notice.

Madonna had teased her appearance in support of Hillary Clinton on the eve of the general election days ago — but withheld the time and location until just moments before she began singing.

As word spread via social media, fans flocked to the park near Greenwich Village.

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“Meet me in Washington Square Park at 7:30. Let’s go hard for Hillary Clinton,” the 58-year-old wrote underneath of a picture of herself in a red-white-and blue cap that was dotted with white stars that she posted on Instagram.

Cheers and screams broke out when the singer danced through the crowd — blond hair flying under her flag-patterned hat — and stepped up to a small stage with just a few bare-bones musicians backing her.

“This is very exciting,” she said, her long aviator-style jacket almost covering ripped black jeans.

The “Vogue” singer ran through five songs in about 20 minutes — hitting “Express Yourself,” “Rebel Heart,” “Like a Prayer” and throwing in a cover of John Lennon’s “Imagine.”

She closed the performance by extolling the talents of the Democratic presidential nominee and telling the crowd, “We must keep America the great country that it is.”

Madonna has been a strong supporter of Clinton’s, officially endorsing her in September.

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“It’s about unifying us. It’s about keeping America great. Not making America great,” she said, doling out hugs to the crowd around several burly security guards.

Vida Loose, 18, a New York University student from California, got there early enough to see Madonna walk the crowd, joking with her fans.

“She talked about love and unity and equality in the face of an awful Donald Trump … She looked great. I can’t believe she’s 57 or something,’ Loose said.

Luana Psaros, 19, studying musical theater at NYU, said it was a momentous — if brief — experience.

“It was really quick. She summarized everything well. It was just an intimate space with a lot of people,” she said.

Queens photo producer Melissa Chapman, 34, got off the train to catch the last 10 minutes of Madonna’s free show.

“You could feel an energy in here. Everyone was buzzing,” Chapman said.

Her friend, Kimberly Witinski, 30, also from Queens, was so excited she climbed on Chapman’s back to try for a blurry photo.

“I thought it was amazing. Anything Madonna does is amazing. It was huge,” Witinski said. 

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