Maloney has consistently received a poor response on the talent show, with Louis Walsh branding him a "cabaret act" earlier in the competition.
However, after singing 'You Raise Me Up', judges Nicole Scherzinger, Tulisa, Louis Walsh and mentor Gary Barlow told Maloney how much they enjoyed it.
Walsh said that it was a "great song choice", while insisting it was a hit for his band Westlife instead of original artist Josh Groban.
The 60-year-old judge added: "I can see you on the West End. I can see Andrew Lloyd Webber putting you on the stage as Phantom [in musical Phantom of the Opera]. You're going to change your life, you're going to change your nan's life."
Meanwhile, Scherzinger said: "Christopher, that is a very hard song to sing. And after that vocal performance, you have proved that you have earned your place here."
Tulisa added: "I really enjoyed that performance, no buts. Everything about that was very you and I think you've done everything you can to get into the final."
Maloney said that he was dedicating the performance to his grandmother, telling her in a pre-recorded segment for the show: "You've believed in me all these years and you're my number one fan."
Watch Christopher Maloney perform 'You Raise Me Up' on The X Factor below:
Photo gallery - The X Factor semi-final: