AceShowbiz -

Simon Cowell reportedly is having doubts of his initial choice to judge the U.S. version of "The X Factor". The producer had once selected Cheryl Cole to accompany him on the panel along with Nicole Scherzinger but words on the street are, he is afraid that Cole is not as popular Stateside as she is in Britain.

Consequently, he is forced to look for an alternative and rumor has it, Mariah Carey was it. Cowell indeed said last week that he had received a call from an A-list celebrity. "We had a phone call from someone on the weekend, someone very well known who out of the blue wanted to be a judge on the show. Literally out of the blue, and it's one of the most famous singers in the world," he gushed.

Over the weekend, Cowell had expressed his interest in Carey. Saying "who knows" to Cole's casting, Cowell told News of the World, "Mariah Carey would be an amazing addition to the US show. And she's exactly the right caliber of star that we want for the show."

Carey's husband, Nick Cannon, also works for Cowell. He is the host of summer filler "America's Got Talent" which is also Cowell's brainchild.