Patti LaBelle didn’t need a microphone at the Convention Center, Thursday. (All photos by Marvin Joseph/TWP)

As the North Carolina R&B singer delivered a gospel rendition of his 2008 song “Fine Again,” his rough-hewn tenor soared through Hall E of the Washington Convention Center on Thursday night at a concert celebrating this week’s Martin Luther King Jr. Memorial dedication.

But as Hamilton pushed the song higher, the mood still felt a little down. Moments before the performance, organizers announced that Sunday’s dedication festivities on the National Mall had been canceled in preparation for Hurricane Irene. Meantime, a scheduled Thursday night performance from Anita Baker had been nixed. And when the concert began, there were more empty seats in the room than people.

Anthony Hamilton, bottom right, gave a spirited performance of “Fine Again.”

There were some big names in the audience, too. Jesse Jackson, Cuba Gooding Jr., Michael Eric Dyson and Jackie Joyner-Kersee were all recognized from the stage by actor Wren Troy Brown, the evening’s emcee.

The concert, dubbed “The Message in the Music,” promised songs from the Civil Rights era, but the evening’s younger artists chose to look forward, treating King’s legacy like a living, breathing thing.

India.Arie was joined by pianist Idan Raichel.

Three of Naturally 7 on Thursday.

Eddie Levert had the crowd on its feet.

They may have been warming up for LaBelle, who closed the show see-sawing between grandiosity and grace during “Two Steps Away” before offering a volcanic take on “Somewhere Over the Rainbow.”

Between her biggest, highest, loudest notes, she offered condolences for the late Nick Ashford, encouraged tolerence and asked for the safe return of our soldiers fighting overseas.

But those heartfelt sentiments didn’t come without a little showboating. LaBelle was only onstage for two songs, but found time to change from high heels to higher heels and primp in front of a hand mirror. At times, she would step away from the microphone and wail at the top of her voice.

You could hear her in the back of the room - a room longer than a football field. You could probably hear her over the rainbow, too.