Lewis is the winner of the third series of The X Factor, beating Ray Quinn in the 2006 final. She’s the second best-selling act (behind, of course, One Direction) to come out of the show.
And Lambert may have only finished runner-up in the 2009 series of American Idol, but he’s released three studio albums and 10 hit singles. He’s now known for performing with band Queen as lead vocalist.
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