"I'm in!" the former Olympian and reality star, 71, wrote on Friday. "Sacramento needs an honest leader with a clear vision."
Well, many people on social media want Jenner, a longtime Republican, out.
Hours after her announcement, "HELL NO" began trending on Twitter with various celebrities weighing in.
"You are running as a Republican?! Republicans deny your existence and are trying to erase trans youth," Alyssa Milano tweeted.
Author and transgender activist Jennifer Finney Boylan also reacted to the news. (Boylan appeared on Jenner's Keeping Up With the Kardashians spinoff show, I Am Cait.)
"I said everything I have to say when I co-starred on her series. She is my friend, but yes, I did once hit her with a rolled up newspaper," Boylan tweeted along with a telling photo.
Kathy Griffin, who is a family friend of the Kardashians, retweeted singer-songwriter Ricky Davila's message.
"As a gay Californian, I'll never vote for Caitlyn Jenner Kardashian. She's unqualified, loathsome, selfish and her views are abhorrent," he wrote, noting how she is surrounding herself with some who are still loyal to Donald Trump. (Jenner was reportedly spotted dining with the former president's campaign manager, Brad Parscale.)
Griffin also called out one of Jenner's campaign images, which features her driving a vintage car with her dog in the passenger seat. (In 2015, Jenner was involved in a multi-vehicle collision on the Pacific Coast Highway in Malibu that killed Kim Howe, 70.)
"Caitlyn driving a car was not the best choice for her official campaign photo," Griffin tweeted.
MSNBC's Joy Reid called Jenner "basically a different Trump — rich celebrity running to try and make Republican fascism flirtation seem cool..."
The Kardashians have yet to weigh in on Jenner's announcement. Although she appeared on a recent episode of Keeping Up With the Kardashians to ask for career advice, a source tells Yahoo Entertainment it's "not likely" Jenner's famous family will offer up much public support.
"I have been a compassionate disrupter throughout my life. ... As Californians, we face a now-or-never opportunity to fundamentally fix our state before it's too late," Jenner said in her announcement. "Taking on entrenched Sacramento politicians and the special interests that fund them requires a fighter who isn’t afraid to do what is right. I am a proven winner and the only outsider who can put an end to Gavin Newsom’s disastrous time as governor."
A formal announcement is expected soon. Jenner's bid comes nearly 20 years after Arnold Schwarzenegger successfully became governor of California during a 2003 recall election.
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