More than two decades after the fact, Kelly Clarkson's groundbreaking American Idol win still looms large as a major moment — both for the singer, her fans and the show itself.

Clarkson was the first-ever Idol winner, beating out runner-up Justin Guarini to win a record contract and launch what would go on to become a massively successful crossover pop career.

On Monday (Sept. 4), Clarkson marked the 21st anniversary of her landmark Idol win on social media.

"21 years," she writes in the caption, sharing a photo of her onstage the night she became American Idol's first-ever champ.

Of course, the vote was fan-determined, and in the comments section of her post, many fans who've been around long enough to vote for her Idol win chimed in with their own memories of the special anniversary.

"I made my whole family vote for you, even my neighbors, lol. I said, Kelly needs to win, she's the one. I was a determined 15-year-old kid," one fan replied in the comments section of her post.

"I voted hundreds of times across 5 phones land and cell," someone else recalls.

"The one and only time America agreed on something and got it right," another adds.

This year, Clarkson's statement to mark her Idol anniversary was brief. However, last year, the singer expounded more on how much the moment meant to her, in celebration of the 20th anniversary of her win on American Idol.

"That moment was the door that opened up so much access and opportunity, and creative partnerships that I will be grateful for all of my days," she reflected at the time. "The family and friendships I have created over these 20 years in music and TV are priceless to me."

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