The search is on for the new David Letterman, and many hope that a woman will take the helm. Here are videos of some of the presenters and comedians tipped to take over...
Joan Rivers, who was once a guest host for her mentor Johnny Carson during the 1980s. But at the age of 80, there are doubts that Rivers will cope witht he gruelling late-night schedule
Ellen Degeneres, 56, who has hosted the Oscars twice and has fronted her own daytime talk show for 10 years
There's a growing lobby for comedian Amy Schumer, who impressed in an appearance on Letterman last week to promote her sketch show, Inside Amy Schumer
Stephen Colbert, who's show The Colbert Report now attracts a bigger a greater audience share in the crucial 18 to 49 age demographic than its broadcast network rivals