Even the ushers dance at a Stevie Wonder show.

At least that’s what they did during and even after Wonder’s emotional and uplifting and inarguably fabulous Wednesday appearance at MGM National Harbor.

Wonder was a frequent visitor to Washington during Barack Obama’s presidency, during which he made several White House appearances to perform and another to pick up his Presidential Medal of Freedom, which honored a career that he began in 1961 as a preteen. He also stopped by the area in 2014 as part of his elongated arena tour in tribute to “Songs in the Key of Life,” his 1976 album that stands as one of his many masterpieces. The set list of his current roadshow, labeled the Song Party Tour, doesn’t concentrate on any particular album, era or even artist. This night featured lots of Wonder classics, some covers, sad tears, and — foremost — dancing.

The party tour comes at a time when Wonder, 68, has been grieving, much of it publicly. He’s admitted being devastated by the recent death of fellow Detroit legend Aretha Franklin, one of his early patrons. On this night, the devastation became manifest while Wonder was doing his mid-’80s ballad (and last pop radio hit), “Overjoyed.”

He suddenly broke away from the regular lyrics and offered up some slow bars of “(You Make Me Feel Like) A Natural Woman,” a Carole King ballad that Franklin made her own with a 1967 single that ranks among the most wonderful songs ever put to record. The big video screens showed streams of tears flowing from behind Wonder’s sunglasses as he sang. They kept rolling down his cheeks as he told of how he wrote “Until You Come Back to Me” for Franklin when he was 15 years old. In wholly objective terms, it is as great as any song or work of art or anything ever produced in the history of humankind.

“Don’t mind my tears!” he shouted after the sadness passed. “I’m not ashamed of it! ’Cause the girls like it!”

He then uplifted everybody’s mood by launching into “Master Blaster,” his 1980 tribute to Bob Marley, another dead artist whom Wonder was once very close to. He took another memorial dance break to ask a DJ on stage to play “Billie Jean” for Michael Jackson’s birthday, and made a special request to hear some Chuck Brown, the departed D.C. go-go king. He dedicated his own performance of John Lennon’s “Imagine” to John McCain.

Amid the kinetic heaviness, he delivered an intense and abstract version of “The Star Spangled Banner” on harmonica. Almost all fans were sitting when it began and throughout the song’s performance. In context, with this particular tune being used much more to cause rancor than inspire patriotism among Americans these days, rendering it as a piece of music rather than an anthem seemed like a sly move.

Everybody in the house stood, unified by awe if nothing else, when he played the last note.

The show wasn’t defined only by its maudlin moments, however. Wonder, for all his years as a pop statesman, his serene aura and Wise Man image, still has no qualms about flaunting his goofy side. Before the sentimental funk classic, “I Wish,” he said he needed to sip a beverage to soothe his vocal cords, then spent a couple minutes gargling and making slurping noises into the microphone. From his giggles, punctuated by a belch, it eventually became clear that making the boyish sounds was the whole point of the exercise.

His attempts to divide crowd singalongs along gender lines during “Don’t You Worry ’Bout a Thing” and “All I Do” were complete failures from a technical standpoint, but Wonder was fully entertained by hearing fans sing his songs in the key of off, which allowed him to mock the amateur crooners responsible for the disharmonies.

Nearly 2½ hours after he took the stage, Wonder repeated a plea to “make love great again!” several times, then banged out the iconic opening riff to his traditional and impossible-to-top show closer, “Superstition.” The whole house was up and shaking one last time. A wondrous night, one could say.