O'Brien's last show is expected to air this Friday. Tonight's scheduled guests are director Quentin Tarantino and actor Paul Bettany. Oscar-winner Tom Hanks and comic actor Will Ferrell are slated to appear on O'Brien's last show. Ferrell was O'Brien's first guest when he made his debut as the Tonight Show's host in June.
NBC's late-night comedy lineup first took a dramatic turn earlier this month when, amid flagging ratings for "The Tonight Show" and Leno's 10 p.m. "Jay Leno Show," NBC announced that it wanted to move Leno's program to 11:35 and push O'Brien's show back to 12:05 a.m.
Last week, O'Brien issued a statement rejecting the plan, saying the shift would "seriously damage what I consider to be the greatest franchise in the history of broadcasting."
(For O'Brien's full statement, click here.)
Despite lackluster ratings during his first seven months on the job, O'Brien has seen a groundswell of public support as the details of the scheduling negotiations emerged. O'Brien fans in New York, Chicago, Los Angeles and Seattle organized public demonstrations Monday to "show love" for O'Brien, whom many fans affectionately refer to as "CoCo."
A grateful O'Brien aired footage of Los Angeles protesters rallying in the pouring rain by NBC's studios.
Rally organizer Mike Mitchell, the administrator of the Facebook group "I'm With COCO," acknowledged in an interview with ABCNews.com that the demonstrations likely wouldn't change NBC's plans.
"I don't think we're going to change NBC's stance on what they want to do with late night -- I think that's already been inked," he said. "I think hopefully we're going to show Conan's got a huge following and we're behind him no matter where he ends up."
Mitchell, 27, a Los Angeles-based freelance illustrator, quickly found himself close to the O'Brien controversy after he created a black, white and orange illustration of the comedian emblazoned with the "I'm With COCO" slogan.
The Facebook group has grown from 200 members to more than 315,000 in a matter of days, he said.
"Now is just a good time to support him because he's kind of been put in a tough spot and people can relate to his situation," he said. "Everybody's had a bad boss that has maybe put them in a position that they didn't want to be in."
Mitchell said he has heard from members of O'Brien's crew who have also voiced their support for the host.
"Everybody on the show has 'I'm With CoCo' avatar on Facebook," Mitchell said, referring to his famous image. "I know personally they want to follow Conan wherever he goes. … They love him and they respect him."
O'Brien's ratings, meanwhile, surged last week as the host peppered his show with jokes at his network's expense, at one point suggesting that NBC considered him such an idiot that he might be qualified to actually run the network.
O'Brien's Friday show, according to a preliminary Nielsen Company estimate, drew more than 4 million viewers, jumping more 50 percent from late last month. (By comparison, CBS's Letterman drew nearly 4.2 million viewers, a drop from earlier in the week, while ABC's Nightline also drew just more than 4 million.)
O'Brien's manager, Gavin Polone, told ABCNews.com that part of the reason O'Brien's ratings were lower initially was because of the weak lead-in audience provided to him by Leno's show.