Keibler and boyfriend Clooney hosted an all-star fundraiser for Obama in Los Angeles on Thursday (May 10), which raised $15 million (£9.3 million) for the president's re-election bid.
In an interview with People, the former Dancing with the Stars contestant disclosed that Obama joined Clooney and Tobey Maguire for a basketball game at the actor's home on the morning after the gala.
"I was a cheerleader on the side," Keibler revealed. "George and Obama were on the same team, so they both [won]. It made it easy."
Keibler also said it was "an honour" to have organised a fundraising event for the US leader.
"To have the President at our house was such an unbelievable honour," she added. "I would say that there is such an energy and a presence, and I felt almost speechless."
Obama is expected to attend a re-election benefit thrown by Eva Longoria and Ricky Martin in New York City on Monday (May 14).
Glee co-creator Ryan Murphy has also said that he will host an upcoming Obama campaign event.