Demi Lovato hit the stage at the annual 'Christmas in Washington' special, and the adorable 'X Factor' judge brought her signature rock edge and powerhouse vocals to the table.

Introduced as "French for 'half a Lovato'" by host Conan O'Brien, Dem's presence really was a gift, and it looked like President Obama was even more excited to see her onstage than his own daughters. Check out that smile on his face!

Lovato performed the Mariah Carey Christmas classic 'All I Want for Christmas Is You.' Accompanied by a full choir cloaked in red scarves and green sweaters, Lovato sported a gold studded black leather jacket over a black and gold dress, black tights and sky-high noir heels as she belted out the holiday pop staple. First Lady Michelle Obama even bopped her head along.

The brunette beauty was the top-billed artist on the show, which also included 'Smash' star Megan Hilty, legendary diva Diana Ross and K-Pop sensation (and controversial once-Yankee hater) Psy -- and it's clear to see why. She slayed it!