The number that displays on Ainsley's caller ID when the White House calls is (202) 456-1414. That is the real world telephone number of the White House switchboard.
President Bartlet is drinking from a Dayton Flyers mug. Martin Sheen was born in Dayton, Ohio, home of the University of Dayton Flyers.
The language spoken by Pres. Nimbala (Zakes Mokae) is Setswana. It's an official language in South Africa and Botswana.
In CJ's fish bowl is an elephant, the symbol for the Republican party. Obviously, a correlation to Ainsley being a Republican.
The theme tune used for the fictional TV series "Capital Beat" is the same one used for the real "ITN News at 10" in the UK.