Nick Jonas and N.E.R.D. rapper Pharrell Williams are the lead candidates to fill the two open judge positions on American Idol , sources tell UsMagazine.com . 

An insider tells the website, "Nick is pretty close to signing to be the Idol judge.  They flew him in to L.A. last week for final meetings."  According to another source, Idol producers think Nick "can help bring that younger demo to the show."

Williams is reportedly still negotiating the terms of his contract. "Everything is looking good, but they're still working out details," an insider said.

Mariah Carey has already been confirmed as a new judge, and original Idol judge Randy Jackson is expected to return next season.

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