Mac Miller's live performance of "Knock Knock" in Chicago is a fairly good reflection of what you're in for at one of his concerts: very little gravity, a lot of movement and fans who could easily understudy for the rapper because they know every word to every track.

It's his pumped-up, feel-good presence that puts him on the list of contenders for the [article id="1675391"]Best MTV Live Performance of 2011[/article].

And we totally understand why he made the list. Just last week, when we checked out Mac's set at New York's Best Buy Theater, it wasn't so much a concert as it was a gigantic school's-out-forever party. He proved to be a very capable MC in both the literal and hip-hop definitions, ordering the audience to have fun and delivering tracks from his EPs and LP alike with the backing of a DJ, a handful of friends and a hype man. There were many times during the nearly hour-and-a-half-long set, however, when Miller didn't even need to perform: So dedicated is his following that there was literally not a line that wasn't also uttered by the audience.

Miller took advantage of their skills especially during "Party on Fifth Ave.," as they traded lines during the chorus. The loyal crowd seldom stayed still, dancing and fist-pumping their way through such tracks as a guitar-heavy "Smile Back" and standouts "Donald Trump" and "Frick Park Market."

Only adding to the concert's festive feel was the sing-along Mac performed in the middle of his set. Armed with only a Rickenbacker, Miller blazed through the choruses of such pop standards as Lynyrd Skynyrd's "Sweet Home Alabama" and Biz Markie's "Just a Friend."

By night's end, the lights went up and friends high-fived, still ecstatic that they'd just seen their hero, their heavily tattooed peer who understands their obsessions and obstacles and assures them that, despite it all, everyone's due to have a "Best Day Ever."

That performance and many others have landed Mac a spot on this year's Hottest Breakthrough MCs poll. Support Miller (or your favorite rookie rapper) over on RapFix.MTV.com.

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