Simon Cowell Endorses Crystal Bowersox On ‘Leno’

'American Idol' judge brings his fiancée onstage during lengthy 'Tonight Show' interview.

Simon Cowell paid a visit to NBC on Monday night’s edition of “The Tonight Show With Jay Leno.” During the conversation, the “American Idol” judge and the late-night host discussed Cowell’s looming departure from “American Idol,” his upcoming wedding and whether or not he is “grumpier” this season than last.

“I thought I was in a good mood,” Cowell told Leno, who then ran the clip of Cowell’s reaction to Haeley Vaughn’s rendition of Miley Cyrus’ “The Climb” last week. (The 16-year-old singer’s rendition was deemed “a total mess.”) “Maybe [I'm] a teensy-weensy bit more grumpy,” he admitted.

“I’m always kind of upset at what I said, so when I watch that back I have to apologize to that girl … whatever her name was.” He then paused for a beat and added, “Kidding!”

On the flip side, the sharp-tongued Brit mentioned that he was a fan of Crystal Bowersox , the mother from Ohio who bounced back from illness last week to deliver a stirring rendition of Creedence Clearwater Revival’s “Long as I Can See the Light.”

“I tell you who I like, I like this girl Crystal,” Cowell said. “When I first saw her, I described her as a busker, and I liked the way she handled that, because she admitted that’s what she was. But she’s got some confidence now. She was ill, she’s got over that, she’s got a great voice. She’s different. I like her.”

Cowell told Leno that he felt totally secure in his decision to leave “Idol” at the end of this season, and that he has been advising the producers about finding a replacement. “I basically advised them to find the worst possible person,” he joked. “You don’t want to leave and have the show be successful after you leave.”

They also discussed the rumored feud between Cowell and new judge Ellen DeGeneres. “I thought we were getting along, but then she moved to the other side of the table,” he said. “We get along fine, though I did take it quite personally when she moved away from me. I’m kidding! But she’s getting nearer and working her way back.”

“So by the end of the season, she’ll be in your lap?” Leno asked.

“That’s what normally happens,” Cowell quipped. “That’s what happened with Paula. She ended up on my lap — off the show as well.”

Cowell confirmed to the host that he was indeed engaged, and though he told Leno that he was not comfortable talking about his personal life, the host still called his fiancée, “Idol” lead makeup artist Mezhgan Hussainy, onto the stage. Upon her arrival, Cowell kissed her and allowed her to share his chair.

Leno also asked Cowell if he misses Paula Abdul, who left the show over a contract dispute before the current season started. “I miss Paula,” Cowell admitted. “I talk to Paula all the time. She was great fun, and it is a different show without her. Something will happen with me and her at some point.”

He wouldn’t confirm Abdul’s involvement in the American version of his talent show “The X Factor,” which will debut on Fox in 2011. But he did say that he would definitely work with Abdul in the future.

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