Bernie Sanders may be in Atlanta for tonight's (November 20) Democratic debate, but the presidential nominee hopeful decided to have some fun while he was in town, too.

The 78-year-old Vermont senator attended Ariana Grande's concert on Tuesday night (November 19), and in return received a glowing endorsement from the pop star.

"MY GUY. thank you Senator Sanders for coming to my show, making my whole night and for all that you stand for !" she tweeted alongside photos of herself and Sanders. "@headcountorg and i are doing our best to make you proud. we’ve already registered 20k+ young voters at my shows alone. also i will never smile this hard again promise."

The politician wasn't the only special guest at Grande's Atlanta show. She also surprised fans when her former Victorious co-stars Elizabeth Gillies and Matt Bennett joined her onstage for a mini reunion. Before the pop star hit the stage, "Make It Shine," the show's theme song, rang from the loudspeakers. Bennett then hopped onstage to sing "I Think You're Swell," and Gillies performed "Give It Up" with Grande — a song their characters sang together in the show's first season.

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