Happy Birthday, Katy Perry!

The singer, who turned 31 today, kicked off her celebrations a day early by attending and performing at a political rally in support of Hillary Clinton in Des Moines, Iowa, on Friday. The pop star had the lucky honors of taking over the democratic presidential candidate's Instagram for the day.

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"Katy Perry here, taking over Hills' IG today for the rally in Iowa," she captioned a photo of her campaign-themed nails. "The stage is set, and the nails are pressed. T-minus 1.5 hours before we Roar together. #ImWithHer."

Perry then announced that politics "runs in the family," posting a photo of her niece coloring in a photo of Clinton.

Dressed in a sparkly white Michael Costello gown styled with red, white and blue accessories, the "Dark Horse" singer posed with some of her fellow supporters.

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And, of course, snapped a selfie with Clinton.

Perry took a break from social media to perform for the crowd before the Iowa Democratic Party's annual Jefferson-Jackson Dinner. After Bill Clinton introduced her, Perry belted out hits like "Roar" and "Firework," and encouraged the audience to get out and vote.

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"You have so much power and this is one of the most important elections in over a decade. So much change can happen," Perry said. "I stand and I march with Hillary. I believe in her future, her vision. I believe in her policies. I believe in equal rights for men, women, pay...Thank you for having me, she's my firework."

Before the rally came to an end, Clinton thanked Perry for her efforts. "I have to give a special shout-out to somebody really special, somebody whose birthday is tomorrow, someone who reminds us that sometimes you just have to let them hear you roar," Hillary said. "Katy Perry, thank you for being here."

On Saturday, Clinton took to Instagram to wish Perry an official happy birthday, sharing a photo of the two getting caught in the act of taking a selfie.

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Meanwhile, Perry commented on turning another year older, tweeting, "Omg I have to be an uneven number for a whole year. My OCD is flaring."

The presidential hopeful turns 68 on Monday, and in honor of that, Perry gave her a very special gift as well -- a gold 'POTUS' nameplate necklace.

"My birthday gift to fellow Scorpio, Hillary, says it all," Perry wrote.

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This isn't the first time Clinton has hung out with one of her many celebrity friends recently. In August, she snapped a photo with the queen of selfies, Kim Kardashian. Watch the video below to hear more.

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