Hillary Clinton trolled her Republican rival Donald Trump ahead of tonight's debate by tweeting footage of Barack Obama roasting the billionaire.
Clinton shared footage of the 2011 White House correspondents dinner, during which the President remorselessly skewered mr Trump with a series of barbed comments.
Obama took Trump to task over the businessman's doubt about where he was born.
"No one is prouder to put this birth certificate matter to rest than the Donald.
"That's because he can finally get back to focusing on the issues that matter like did we fake the moon landing, what really happened in Roswell and where are Biggie and Tupac?"
The President that mentioned Trump's credentials and experience, to raucous laughter.
Mr Obama began talking about Trump's actions on The Apprentice. "These are the kinds of decisions that would keep me up at night," he said to applause. "Well handled sir."
Clinton then accused Trump in a separate video of a series of lies about his record on Iraq, Libya and representation of her policies.
Husband Bill Clinton also appeared confident his wife would win the debate.
He tweeted: "Looking forward to tonight's debate knowing that millions of Americans will see the @HillaryClinton I've known for over 40 years."
Mr Trump's own Twitter feed was quieter as the debate loomed.
He wrote that he was handing the account over to his "deplorables".
Trump also pointed out a new poll by Bloomberg showing he had moved two per cent clear of Clinton.
He tweeted: “New national Bloomberg poll just released - thank you! Join the MOVEMENT.”
