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Millions of Americans are expected to watch President Trump's upcoming State of the Union address.

Trump formally accepted newly-sworn-in House Speaker Nancy Pelosi's invitation to hold the event on Jan. 29 in the House chamber. This year, Trump will be speaking to a Democratic-held House. It's also possible the partial government shutdown — which started in late December as lawmakers argued over Trump's $5.7 billion border wall funding — could be ongoing at that time.

From members of Congress to distinguished guests handpicked by the president himself, here are some of the people who are expected to be in the audience.

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The first lady

melania trump

First Lady Melania Trump will have her own viewing box at the State of the Union. (AP)

First lady Melania Trump will have her own viewing box in the gallery of the House chamber.

Guests of the president

A handful of guests will join first lady Melania Trump in the gallery at the president's request. It’s a tradition that was started by President Ronald Reagan in 1982. This year, Trump handpicked 13 special guests including a 9-year-old brain cancer survivor, a former opioid addict, a special agent with the Homeland Security Department's human trafficking unit, among others.

A Marine Corps. veteran, a cop, a welder and the parents of MS-13 victims were among the 15 special guests tapped by the president to attend in 2018.

Cabinet

Members of Trump's Cabinet, and the heads of 15 executive departments, including the acting attorney general, are also invited to attend.

The White House chief of staff, administrator of the Environmental Protection Agency, director of the Office of Management and Budget and the U.S. trade representative have typically had reserved seats at the front of the room.

Supreme Court justices

All nine Supreme Court justices were invited to attend the event, though several are skipping it.

This will be Brett Kavanaugh's first SOTU. Kavanaugh, who was accused of sexual misconduct and faced a lengthy confirmation hearing as Dr. Christine Blasey Ford brought allegations against the federal judge in front of the Senate Judiciary Committee, was chosen by Trump to fill Anthony Kennedy's Supreme Court seat after he announced his retirement from the bench. He was confirmed to the nation's highest court in October with a 50-48 vote.

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Justices Clarence Thomas and Samuel Alito will probably opt to ditch the SOTU. They haven't attended the event in years.

Alito last went in 2010, when he was captured on camera shaking his head and mouthing the words "not true" in response to President Barack Obama's criticism of the court's ruling in the Citizens United campaign finance case.

Ruth Bader Ginsburg was out of town last year. She'll also miss this year's event. Ginsburg missed oral arguments for the first time since she joined the court in 1993 on Dec. 7 as she continues to recover from a recent surgery to remove cancerous growths from her lung.

Members of Congress

Members of the House and Senate will also be in attendance, along with one guest of his or her choosing.

There’s no assigned seating for members, with the exception of House Speaker Nancy Pelosi and Vice President Mike Pence, who will sit directly behind Trump on the dais.

"In accord with longstanding custom and to ensure the continuity of government, one Cabinet secretary does not attend the speech," the Congressional Research Service says. "After Sept. 11, 2001, congressional leadership began designating two members from each house of Congress, representing both parties, to remain absent from the Capitol during the president’s speech."

Some lawmakers have already revealed who their special guests will be.

Democrat Alexandria Ocasio-Cortez invited Ana Maria Archila, a woman who cornered Sen. Jeff Flake on live television to protest his support for Brett Kavanaugh.

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"I never thought I'd be excited about being in the same room with Donald Trump," said Archila, co-executive director of the left-leaning Center for Popular Democracy. Ocasio-Cortez invited her a few weeks ago, she said, adding, "We talked about making sure that we, with our presence, express the dignity of people who are under attack from this administration, the resilience. We will try to communicate that with the way we show up in the space."

Republican Florida Sen. Rick Scott announced he's taking Andrew Pollack, the father of a teenager who died in the Parkland school shooting.

Rep. Bonnie Watson Coleman, D- N.J., invited Victorina Morales, a Guatemalan woman living in the U.S. illegally who reportedly was fired from the Trump National Golf Club.

Sen. Kamala Harris, D-Calif., who is running for president in 2020, invited Trisha Pesiri-Dybvik, an air traffic controller who lost her home in the 2017 Thomas fire in Southern California.

“Trisha Pesiri-Dybvik was one of the more than 800,000 federal workers whose paychecks were withheld during the shutdown — and it happened while her family was still recovering from losing their home in the Thomas Fire,” Harris wrote on Twitter, adding she was a government employee impacted by the shutdown. “I’m honored she will join me at the State of the Union.”

Rep. Rodney Davis, R-Illinois, offered a spot to Taylorville Fire Chief Mike Crews who "undoubtedly saved lives" after a tornado struck his hometown.

Joint Chiefs of Staff

Members of the Joint Chiefs of Staff and senior uniformed leaders in the Defense Department who help advise the president and his staff on military matters will also attend the address.

Fox News' Andrew O'Reilly and The Associated Press contributed to this report.