http://www.msnbc.msn.com/id/29718457/An NBC
spokesperson says she believes this is the first time a sitting president has agreed to appear on the "Tonight Show." It may also be a first for any late-night broadcast. The network, however, is certain that it's a first for Leno, who's helmed the show for 17 years.
(Msnbc.com is a joint venture between Microsoft and NBC Universal)
Obama's last appearance on the show was back in 2007 — in the midst of Obama's ultimately successful presidential campaign.
At the time, then-Sen. Hillary Rodham Clinton was surging the polls. "Hillary is not the first politician in Washington to declare mission accomplished a little too soon," Obama joked.