First Lady Michelle Obama said her husband - a recent singing sensation - doesn't hesitate to "show off his lungs" and sings to her all the time. ?

President Obama proved his vocal ability when he sang a few lines of Al Green's "Let's Stay Together" at a campaign event earlier this month.

?"That was completely spontaneous," Mrs. Obama told Jay Leno in an interview on NBC's "The Tonight Show" on Tuesday night. "I didn't even hear about it until it got on YouTube, but he does have a beautiful voice, and he sings to me all the time." ?

While the First Lady admitted, "I can't sing," she said the president doesn't "hesitate to show off his lungs to his wife. He's good." ?

"Let's Stay Together" is apparently one of the president's signature songs. "I knew when people said he sang, I thought I'll bet he sang Al Green," Mrs. Obama said. "He sings a lot of Al Green, Marvin Gay, a little Stevie. He likes the classics." ?

First daughters Malia and Sasha, however, may not be big fans of their dad's public crooning.

"Anything we do is highly embarrassing. They just want us to be very quiet, very quiet," Mrs. Obama said.