Conan O'Brien won't be performing at the White House Correspondents' Association Dinner until Saturday night, but he's already in the nation's capital, goofing around -- as shown in this photo he tweeted Friday.

"Practicing my opening 'Goofy Sunglasses' bit," he noted in the pic's caption.

This will be Conan's second time on the Dinner dais, having performed there originally in 1995, when President Clinton was in office. He told Politico that having the leader of the free world at his elbow was actually helpful: "Clinton was really laughing and he gets really red in the face when he laughs, and at one point he was hitting the table and I thought, 'This is great!' ... I definitely wouldn’t want to do my show every night with the president of the United States sitting next to me, chewing Nicorette. But it certainly amps things up."

The White House Correspondents' Dinner will be shown on several networks on Saturday night and O'Brien is expected to appear at 10 p.m. ET. Check back on TODAY.com for a roundup of the funniest moments!

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Imeh Akpanudosen / Getty Images

Lindsay Lohan.

To the bewilderment of some, Lindsay Lohan and Kim Kardashian will be among the celebrities heading to Washington on Saturday for the annual White House Correspondents Dinner, attending as guests of Fox News Channel.

Kardashian was invited by the network itself, which has included her in the past; Lohan will attend as personal guest of news anchor Greta Van Susteren.

Considering Lohan’s recent history of drug and alcohol abuse, and time spent in jail, it’s primarily this latter move that caught people off guard, given the fact Van Susteren recently spouted off on the dinner’s original host, comedian Louis C.K., because he uses foul language. The anchor said she felt he was an inappropriate emcee because his jokes were derogatory towards women, and indicated she would boycott the event should he remain on board.

Soon thereafter, Louis C.K. declined the gig and was replaced by talk show host Jimmy Kimmel.

In response to the Lohan news on Thursday, Meghan McCain gave her assessment of the matter, tweeting, “Let me get this straight Greta Van [Susteren] is bringing Lindsay Lohan to the WHC Dinner but has a moral offense to [Louis] C.K?”

The conservative journalist and daughter of Sen. John McCain promptly found a bandwagon amongst her following.

Scott Shields tweeted in response, “Sure. A comedian using bad words is unacceptable, while a celebrity with substance abuse issues is hilarious. America, 2012.”

Added Joey Guzman, “Thank you! She’s offended by someone who's a comedian but is cool with someone who's life has been a comedy ... wtf?”

The Fox host later explained herself to TMZ, referencing news from Monday that Lohan would play Elizabeth Taylor in the upcoming Lifetime movie, “Liz and Dick.”

“I love comebacks, and I'd like her to succeed," remarked Van Susteren, who was also the one that invited Kardashian in 2010. "She's got a new movie and I'm hoping things work out for her."

Though the typical crowd at the event varies from A-listers down, the rest of the attendants this year don’t spark as much debate. Reports People, additional guests include George Clooney, Josh Hutcherson, Charlize Theron, Sofia Vergara, Viola Davis, Daniel Day-Lewis, Dakota Fanning, Jason Schwartzman, Aziz Ansari, Anna Paquin and Stephen Moyer.

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