Recording artist Kelly Clarkson performs at Hammerstein Ballroom on October 6, 2009 in New York City. (Getty Images)more pics »Kelly Clarkson (From 'American Idol')Kelly Clarkson and her fellow American Idol winners took the stage during the show's finale on Wednesday to sing "Together We Are One" for departing judge Simon Cowell. The first-season winner has changed since her Idol days, but she still commands a faithful fanbase that no doubt cheered her appearance on the show.
Kelly opened the song followed by season two winner Ruben Studdard and season three winner Fantasia Barrino. The only Idol winner who couldn't make it was season seven's David Cook, who had already scheduled a charity event in his native Kansas City the night of the show. On wednesday night, David tweeted: "Congrats to Lee Dewyze! So sorry I could be there to see all my fellow idols. I'm there in spirit!" Check out the video of Kelly Clarkson and a stage packed with Idol alumni sing "We Are One."