VIDEO: Fifth Harmony Cover Mariah Carey Holiday Classic 'All I Want For Christmas'

Fifth Harmony get into holiday spirit with their cover of Mariah Carey's 1994 holiday classic, "All I Want For Christmas Is You." Check out the video!

"I can feel a wave beginning behind this group," said THE X FACTOR creator and judge Simon Cowell before Fifth Harmony performed their version of Kelly Clarkson's "Stronger" on the show last year. The music mogul knows talent and chemistry when he sees it. (This is, after all, the man who assembled One Direction.) Cowell decided that individual contestants Dinah Jane Hansen, Lauren Jauregui, Ally Brooke, Normani Kordei, and Camila Cabello were too special to let go, so at the end of the show's Boot Camp week, the five young women became Fifth Harmony. With their show-stopping vocals, undeniable charisma, and genuine sisterly bond, the "fearsome fivesome" (as they became known) endeared themselves to viewers across the country. Fifth Harmony delivered electrifying versions of Adele's "Set Fire To The Rain," Ellie Goulding's "Anything Can Happen," and Demi Lovato's "Give Your Heart A Break," and revealed their personal journeys to audiences week after week.

"I knew from the girls' first performance at judges' homes in Miami that we'd done the right thing," Cowell says. "The chemistry between the Fifth Harmony girls both on and off stage is fantastic. They are really great girls who have become best friends. They're fun to be around and most importantly, they are all incredibly talented."

Since THE X FACTOR wrapped last December, the group's fanbase has grown rapidly. The covers they post on their official Youtube channel (Rihanna's "Stay," Ed Sheeran's "Lego House") routinely rack up millions of views. Not only does Fifth Harmony trend worldwide nearly every week on Twitter, where the girls engage non-stop with their followers, but the group also draws thousands of female fans of all ages, who call themselves "Harmonizers." "We don't really think of them as fans," Normani says. "They're more like friends who support us." The strong bond Fifth Harmony has forged with their audience will serve the group well as they begin to show the world what they can do post X Factor, starting with their debut single "Miss Movin' On," an epic, empowering pop anthem about letting go and being independent.

Their debut EP Better Together, which was released October 22, 2013, skyrocketed to #2 on iTunes and now officially lands the group their first TOP TEN album, which debuted at #6 on the Billboard Top 200 Chart. Featuring five brand new songs and their smash hit "Miss Movin' On"; it's a diverse, dynamic, and delightful introduction to America's only teen pop female vocal group. The girls just announced that their first single off their EP is "Don't Want To Dance Alone", an upbeat, party tune that will make everyone want to get onto the dance floor.

The girls will now additionally release four new EP editions. Their Spanish EP, "Juntos" and "Juntos Acoustic" were released, November 11th. "Better Together Acoustic" will be released on November 19th and "Better Together The Remixes" will be released on November 25th.

The girls have been handpicked to be a part of Disney's "Next Big Thing" Campaign, MTV & Pop Tarts "Crazy Good VMA Concert", and won the fan-voted Vevo's Lift Artist Award. Cumulatively, they have 70 million total Youtube views, 625,000-plus Facebook "likes", and over 863,000 Twitter followers.

Since the EP release the girls embarked on their first headlining tour, making stops throughout the United States and Canada. During the holiday season, they will be performing at Jingle Ball Concerts around the country with Miley Cyrus, Austin Mahone and many more. In 2014, Fifth Harmony will be joining Demi Lovato on her Neon Lights Tour.

Bio: Fifth Harmony Official Site