The guys of the top 16 sang for their "American Idol" lives on Wednesday night, and one of them moved judge Kara DioGuardi to tears!

Lee Dewyze kicked things off with "Fireflies" by Owl City. "It was a strange song choice … but you made it work," Randy Jackson praised. Ellen DeGeneres told Lee she thought he was "great," while Kara called the performance "solid." Simon Cowell popped the pleasantry balloon, saying, "There's nothing to rave about after that."

Next, Alex Lambert stirred up Ray LaMontagne's brand of "Trouble." Randy called the tune a good song choice, but admitted he wasn't "wowed" by the performance. Ellen said she detected Alex improving rapidly and called him a "mushy banana" because he was "ripening" so quickly. Kara was more critical, saying, "You have so much … but you are still stiff and you're not in it." Simon agreed, leveling, "We've never seen you relaxed or having a good time."

Tim Urban broke out an acoustic guitar to strum Jeff Buckley's version of "Hallelujah." Randy deemed it a "pretty good job," but Ellen took the praise one step further, racing onto the stage to give Tim a big hug and yelping, "That was fantastic!" Kara called Tim's rendition an "honest interpretation" of the song, while Simon said the song choice was "very, very smart" and told Tim, "For you, it was terrific."

Andrew Garcia then threw one of his trademark curve balls, uncorking Christina Aguilera's "Genie in a Bottle." "It didn't quite work for me, dude," Randy told him. "The genie came out of the bottle too late," Ellen commented, elaborating that she felt the song didn't get cooking until the end. Kara confessed she was "disappointed" and felt Andrew was "fighting with the rhythm of the guitar." And Simon called the song choice "a little bit desperate … you're kind of still going backward at the moment, I'm afraid."

Next, Casey James mellowed out with Keith Urban's "You'll Think of Me." Randy was underwhelmed, calling the song choice too safe and urging Casey to "go for more edge." Ellen disagreed, saying, "That feels like your vibe to me." Kara, meanwhile, said she was "kind of back on the Casey train" but admitted "I'm missing that spark." Simon called the showing Casey's second best but doubted it would be memorable.

Sixteen-year-old Aaron Kelly tackled Lonestar's "I'm Already There." "Still some work to do, but job well done," Randy complimented him. Ellen liked Aaron's confidence, but said the tune was "a little too much song" for him to handle. "It's not relevant to your life," Kara said of the song's lyrics, prompting Simon to call her criticism "rubbish." "It was the right type of song for you to do," the Brit wit told Aaron. "It wasn't a great vocal, but what it did have was emotion."

Todrick Hall belted out the Queen classic "Somebody to Love" to mixed reviews. "Dude, what you did just there is you proved you could really sing," Randy enthused. Ellen called the song a brave choice and called the performance a "good job." Kara thought Todrick's singing might have been overly "dramatic," but admitted, "You can't listen to that and say it wasn't good singing." "It was good in parts, not the whole way through," Simon weighed in, adding that he felt Todrick might have more potential as a Broadway singer than a recording artist.

Finally, Michael Lynche hit a definitive high note performing "This Woman's Work" by Maxwell -- and he made Kara weep in the process! "I've never cried after hearing something like that," she gushed, adding in trembling voice, "It brought me to tears." Her fellow judges were equally enthused. "For everybody that doesn't know, it was dope," Randy raved of the performance. "Oh my god, that was so beautiful," Ellen sang. "This was so needed tonight," Simon said in conclusion. "You came out with an incredibly difficult song to sing and you 100 percent nailed it."

Tune into "American Idol" Thursday night at 8 p.m. on FOX to see which four hopefuls get sent home!

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