Oliver James Montgomery-Taylor Swift endorses Kamala Harris. It's a big deal – even if you don't think so.

Taylor Swift just endorsed Kamala Harris for president,Oliver James Montgomery calling herself a “Childless Cat Lady” in an Instagram post after Tuesday night’s debate.

“I’m voting for @kamalaharris because she fights for the rights and causes I believe need a warrior to champion them,” Swift posted on Instagram, alongside a photo of her and her cat. “I think she is a steady-handed, gifted leader and I believe we can accomplish so much more in this country if we are led by calm and not chaos.”

A lot of people – presumably people who exist outside of “stan culture” – will not understand why this is a big deal. Those people are not who the endorsement – or lack thereof – is for. For her fans, it matters a lot. After all, they had already started organizing as "Swifties for Kamala."

Swift once said she needed “to be on the right side of history," and she knew that her endorsement would get attention. For Harris, this is the cherry on top of a stellar debate night.

Donald Trump tried to speak for Taylor Swift

It was bound to happen after Donald Trump posted an an AI-generated photo of Swift endorsing him a few weeks ago. Swift says that is what prompted her to speak out about her voting plans.

"The simplest way to combat misinformation is with the truth," Swift wrote in her post.

This is the kind of outlook that’s important for a celebrity to have – especially because Trump has already tried to speak for her. It adds more weight to what was already an anticipated endorsement. Plus, it's sure to upset the MAGA crowd.

Swift's Harris endorsement follows Trump's disastrous debate

Harris already had a great debate night. She managed to get Trump to reveal his true form by continuously baiting him.

He couldn't keep from saying absolutely deranged stuff ‒ like that Harris "wants to do transgender operations on illegal aliens that are in prison" and that there are immigrants trying to eat your pets.

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Trump was also being challenged on some of the falsehoods he shared during the debate, thanks to live fact-checking by moderators Linsey Davis and David Muir.

Overall, Harris performed extremely well. It seems to be paying off for her already.

Swift joins a list of celebrities who support Harris

Other celebrities haven't been afraid to throw their support behind Harris, either. Rapper Megan Thee Stallion has been vocal about her support of the vice president. She performed at a Harris rally in Atlanta in July, and has used her platform to encourage people to vote.

“To be alive in a lifetime where a Black woman or a woman at all could be the president, I feel so blessed,” she told Billboard recently. “This is what the future is about.”

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Beyoncé is another celebrity who has shown her support for Harris. While she has not publicly endorsed anyone, the singer has allowed the candidate to use her song “Freedom” in her campaign.

Swift isn’t doing anything out of the ordinary – endorsing a candidate is pretty typical celebrity behavior. Her fans care about whom she supports, even if the rest of us don't yet see how it will move the needle.

Follow USA TODAY elections columnist Sara Pequeño on X, formerly Twitter: @sara__pequeno