President Obama sang a few bars of the blues classic with B.B. King and Mick Jagger. (AP)

This is the second time he’s sung in public in 2012, after a clip of him singing Al Green’s “Let’s Stay Together” went viral earlier this year. In an election year, with rival singing Republicans vying for the White House, we bet it’s not the last time we hear our president’s crooning voice. But if the campaign becomes one big karaoke night, what should the president sing next?

Washington Post music critic Chris Richards reviewed the show in the White House:

As the evening’s performers finished off “Sweet Home Chicago,” [Buddy] Guy summoned the president to the stage. “I heard you singing Al Green,” he said, referring to Obama’s recent crooning at the Apollo Theater. “You done started something, and you gotta keep it up now!”

For a moment, the president appeared reluctant — who could follow Mick? — but he grabbed the microphone to trade a few lines with King: “Come on, baby don’t you want to go, [back to that same old place], sweet home Chicago.”

Richards has previously written that Obama’s voice was “promising,” and that it was better than Mitt Romney’s rendition of “America the Beautiful,” but that neither candidate was able to best former candidate Herman Cain’s song “Imagine There’s No Pizza,” a clip that went viral in 2011. Other candidates have sung, danced and played music, but none have been as popular.

Although some clever editing depicted him singing Lady Gaga’s “Born This Way” once, it’s not a performance he would put on in real life. Obama’s musical comfort zone seems to be in the Motown, soul, rhythm and blues categories of music. Looking at his campaign playlist, many of the tunes are too pop or country, and some of the R&B songs, like the Impressions’ “Keep on Pushing,” are out of his range.

He also has to consider the message of the lyrics of whatever he sings — for example, though the Temptations’ “Ain’t Too Proud to Beg,” and Marvin Gaye’s ”What’s Going On” are two of the best Motown songs of all time, they wouldn’t be appropriate for a politician seeking reelection. He could avoid controversy by sticking to love songs, and serenading Michelle.

What do you think President Obama should sing next? Leave your requests in the comments.