Aretha Franklin punched her fist in the air Monday night and yelled: "Tomorrow!"

She didn't need to say Barack Obama's name. The crowd roared its approval. It was an annual Martin Luther King Jr. Day concert, not an inaugural event, but thoughts of Obama's historic day ahead were on everyone's mind.

"Are we ready to Barack and roll?" asked a member of "Nuttin' But Stringz," the crowd-pleasing duo from Julliard (and "America's Got Talent") that infuses classical violin playing with R&B and hip hop.

"We're introducing a whole new leader into the world."

The audience roared then too.

Also performing in the free concert at the John F. Kennedy Centre for the Performing Arts was the Let Freedom Ring Choir, a hugely spirited group made up partly of Georgetown University students, faculty and staff.

The singers seemed thrilled to be singing with Franklin, who, not coincidentally, was getting ready to sing the next day at Obama's swearing-in ceremony.

Dressed in a flame-red gown, Franklin treated the crowd to half a dozen numbers, including "Old Landmark," "Precious Memories," "Chain of Fools" and an encore of "Battle Hymn of the Republic."

Georgetown University, which joined with the Kennedy Centre to put on the event, also presented an award to Marian Wright Edelman, president of the Children's Defence Fund.