David Letterman has been inching closer to Jay Leno for the better part of a year among key 18-49 viewers.

Now in the key November sweep period, CBS' "Late Show with David Letterman" has topped NBC's "The Tonight Show with Jay Leno" -- 1.19 million (0.9 rating/4 share) to 1.08 million 18-49 viewers (0.8 rating/3 share). CBS says this is the first time it had happened since 1994. Still, Leno is ahead in terms of overall viewers: 3.65 million to 3.49 million. Letterman and Leno tied among young audiences 18-34, each with a 0.5/2 for the November sweep period which runs Oct. 27 through Nov. 23.

When looking at overall late night programming, ABC's "Nightline" continues to top all comers -- an 1.26 million average among 18-49 viewers and 4.12 overall viewers. ABC's "JKL," which follows "Nightline," also posted a decent November -- up 7% in total viewers to 1.99 million from a year ago, as well as averaging 810,000 18-49ers for the month. --Wayne Friedman