Barack and Michelle Obama slow-danced their way into their next four years in the White House at a monster inaugural ball featuring some of the biggest stars in popular music today.
Like the king and queen of a high school prom, the president and first lady flashed awkward smiles as they held each other closely and swayed to Jennifer Hudson covering Al Green's 1972 soul classic "Let's Stay Together."
The black-tie and sequined crowd of up to 40,000 in the dark belly of Washington's Convention Center downtown cheered wildly, raising their hands as one to capture the moment on their digital cameras and smartphones.
For her choice of gown, Michelle Obama stayed loyal to Jason Wu, choosing the young Taiwanese-born, New York-based designer for her much-anticipated inaugural ball dress -- just as she did four years ago.
A fashion trend-setter and champion of up-and-coming designers, she matched the arresting ruby-colored, halter-top chiffon and velvet gown with Jimmy Choo shoes and a Kimberly McDonald diamond-embellished ring.
"Just danced to 'Let's Stay Together' with the love of my life and the President of the United States," she said via Twitter right after stepping off the stage. "I'm so proud of Barack."
Wu, who dressed the first lady in a one-shouldered white gown for her 2009 inaugural balls, was unaware until the last minute that he was, once again, her choice for the big night. "#Inshock!!!" he hashtagged on his Twitter feed.
Earlier in the day, for the presidential public oath-taking on the steps of the Capitol, the first lady bundled up against the near-freezing temperatures in a navy Thom Browne coat and dress with a J.Crew belt and gloves.
In contrast to the 10 official inaugural balls that followed his historic inauguration four years ago as the first black US president, Obama favored one jumbo soiree this time -- open to anyone fast enough to snap up the $60 tickets online -- plus a smaller affair for the armed forces by invitation only.
The Obamas, running late, had yet to arrive at the convention center when Alicia Keys got the party started by sitting at an electric piano and reworking the title track of her latest album "Girl on Fire."
"He's president and he's on fire... Ohhhh-bama's on fire," she sang. She then went on to affectionately rejig one verse: "Everybody knows Michelle's his girl/together they run the world."
Next on stage were Mexican rockers Mana, in a nod to Latinos whose vote helped win Obama a second term, before Brad Paisley delivered a powerful country set including his current chart-topper "Southern Comfort Zone."
"Our democracy is the envy of the world, and tonight we celebrate by getting drunk in a huge convention center," said Paisley between songs in the best quip of the night.
Other performers included the legendary Stevie Wonder, an indefatigable Obama supporter who took the stage after the presidential couple's twirl, and Grammy-nominated hipster indie favorites Fun.
There was nothing glamorous about the catering -- beer and sparkling wine in plastic cups and peanuts and pretzels on paper plates. But if Obama's supporters were disappointed, they didn't let on.
"It's a bargain for an event of a lifetime," Washington financial securities lawyer Kosha Dalal told AFP by the bullpen where organizers sequestered accredited journalists.
It was her first inaugural ball.
"We're very big supporters of president Obama and we really wanted to be here," added Amy Kuhn, a staffer at a non-profit organization in New York who traveled down to the capital with her partner Erin Hogeboom.
"I'm really looking to a lot (from the new Obama term) on equality on a wider scale, like gay marriage and women's rights," added Hogeboom, a graduate student in global affairs.