Elton John Gets Channing Tatum in a Pinch

While performing at a benefit concert at NYC last night, Sir Elton John got very hands on ... with Channing Tatum's talented ass.

Looking like Liza Minnelli in "Cabaret," a sleeveless Tatum backed his thang up into Elton's eager hand at the Revlon Concert for the Rainforest Fund at Carnegie Hall.