The singer has 283 million followers on Instagram and her post received over two million likes in just half an hour.
ADVERTISEMENTTaylor Swift endorsed Kamala Harris for US president shortly after Tuesday night's presidential debate against Donald Trump ended.
“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,” Swift wrote in an Instagram post, which included a link to a voter registration website.
"I'm voting for @kamalaharris because she fights for the rights and causes I believe need a warrior to champion them," she added.
Swift has a dedicated following among young women, a key demographic in the November election, and her latest tour has generated more than €905 million ($1 billion) in ticket sales.
In a half hour, the post received more than 2.3 million likes.
She included a picture of herself holding her cat Benjamin Button, and signed the message “Childless Cat Lady.”
The remark is a reference to comments made by JD Vance, Donald Trump's running mate, about women without children not having an equal stake in the country's future.
A Harris senior campaign official said the endorsement was not coordinated with the campaign.
Tim Walz, Harris’s running mate, appeared to learn about the endorsement in the middle of a live TV interview.
“That was eloquent. And it was clear," Walz said. "And that’s the kind of courage we need in America to stand up.”
Swift wrote that her endorsement was partially prompted by Trump’s decision to post AI-generated pictures suggesting that she had endorsed him. One showed Swift dressed as Uncle Sam, and the text said “Taylor wants YOU to VOTE for DONALD TRUMP.”
Trump's posts “brought me to the conclusion that I need to be very transparent about my actual plans for this election as a voter,” Swift wrote. She added: "I’ve done my research, and I’ve made my choice."
The Trump campaign dismissed Swift's endorsement.
“This is further evidence that the Democrat Party has unfortunately become a party of the wealthy elites,” said spokesperson Karoline Leavitt.
“There’s many Swifties for Trump out there in America,” she said, herself included.
ADVERTISEMENTSwift's endorsement was not exactly a surprise. In 2020, she supported President Joe Biden, and she cheered for Harris in her debate against then-Vice President Mike Pence.
She also was openly critical of Trump, saying he had stoked “the fires of white supremacy and racism.”