Christina Aguilera dressed to impress at the opening of the Obama Presidential Center.

The superstar singer wore a semi-sheer Prabal Gurung gown with a long train as she performed “What a Wonderful World” by Louis Armstrong in Chicago on Thursday.

The 45-year-old opted for minimal jewelry, sporting a silver ring on her right finger, while her signature blond hair was curled at the bottom.

Aguilera performed in front of Barack and Michelle Obama and their two daughters to celebrate the opening of the former president’s new 19-acre presidential center on Chicago’s South Side.

Former Obama advisor Valerie Jarrett introduced Aguilera, revealing that they asked her to sing “one of President Obama’s favorite songs,” but the Grammy Award winner told them she had never sang “What a Wonderful World” in public before.

However, Aguilera “came up with a new arrangement” for the event, Jarrett shared.

Aguilera has supported Barack, 64, before, including when she hosted a $1 million Democratic fundraiser that praised the Obama administration’s record in 2015.

Three years later, the “Beautiful” singer performed at a Democratic National Committee (DNC) event, billed as “Evening with Barack Obama,” at a private Beverly Hills residence.

In the last presidential election, Aguilera openly supported Kamala Harris over the eventual victor, Donald Trump.

Other performers on Thursday included Jennifer Hudson, who sang the National Anthem and a cover of “To Dream the Impossible Dream,” followed by The Roots, John Legend, Marc Anthony and U2.

Pearl Jam’s Eddie Vedder also took the stage, joined by young members of the nonprofit Guitars Over Guns.

Tons of stars made it to the opening, such as Oprah, Steven Spielberg, George Lucas, Tom Hanks, Stephen Colbert, David Letterman, Conan O’Brien, Anne Hathaway, Gabrielle Union, Quinta Brunson and Mark Hamill.

The Obama family sat in the audience with Bill and Hillary Clinton and George W. and Laura Bush.

The 44th president’s new center in the city where he once lived features an eight-story museum, a replica Oval Office, an NBA-regulation basketball court, community gardens and branch of the Chicago Public Library.

In his introductory video, Barack spoke about what the South Side of Chicago means to him.

He said that’s where he “started knocking on doors, where I learned to listen and found my voice, where I fell in love with Michelle and built a family and a community and a home.”

“From this place, our circle and our aspirations grew, because the story of the South Side has always been a story and a possibility, and now we start writing a new chapter,” he stated.

The center officially opens to the public on Friday.