Posted on Wed Jan 23, 2013 10:15 AM PDT
Lady Gaga teamed up with legendary crooner Tony Bennett to sing at a private event for Obama's staffers.
The eccentric performer, who wowed in a white Versace dress, belted out "The Lady Is A Tramp" alongside Bennett at the Washington Convention Center.
When President Obama hit the stage, his staffers reportedly sang to him ... "Signed, Sealed, Delivered."
Looks like it was quite the night!
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