The judges had predicted that Mark would be chopped by the audience, and there were gasps from the crowd as it was announced that Chris was out.
He was tearful, but thanked his fans. He said: "I've loved it. Thank you to everyone who voted for me."
Sam is now favourite to win the show, with Michelle in second place. Mark, who sang Blue Christmas, is last.
The judges weren't exactly kind to Mark.
Simon Cowell told him he sounded like a "bloke at an office party."
Ten of the finalists have recorded Happy Christmas (War is Over) as a single, and it's being tipped for the Xmas number one.
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