Not only does this diva have the distinction of being the very first American Idol winner, she’s also one of the most successful. With her powerhouse vocals and down-to-earth charm, Clarkson literally became an overnight sensation on Idol in 2002. Despite an embarrassing big-screen debut in the critically lambasted movie musical Justin to Kelly (which she was contractually obligated to star in opposite runner-up Justin Guarini), Clarkson made 2003 her year, with her best-selling debut album Thankful spawning a number of hit singles. Her 2004 follow-up, Breakaway, was also a smash and earned the Grammy for Best Pop Vocal Album. And she’s maintained steady success since: her albums My December (2007) and All I Ever Wanted (2009) were both critical and commercial hits.