The boyband expressed their support in tonight's (October 6) first live show of the series, which saw Christopher Maloney win the Wildcard vote to become the 13th contestant.
When Dermot O'Leary asked Louis Tomlinson for the group's favourite acts, the popstar replied: "We all absolutely love James Arthur. I think he's unbelievable."
Harry Styles then agreed: "Yeah, James."
After a performance in which Arthur sang and rapped Kelly Clarkson's 'Stronger', Louis Walsh said: "We've found ourselves a brand new recording star."
> 'X Factor' Live Shows Week One - Live Blog
Tulisa Contostavlos stated that he would be "first choice" if she could have a male in her category, but Gary Barlow suggested that the contestant's "edges are starting to be rounded off", adding that Arthur had to "disagree" and "do it your own way".
Arthur responded to the seeming criticism by saying: "You don't know what goes on behind the scenes, and I made that song my own."
Photo gallery - The X Factor first show:
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