CJ's secret service codename is Flamingo, Zoey's is Book Bag, Sam Seaborn's was Princeton, and the President is either Eagle or Liberty (depending on the episode). Bartlet's grandson Gus (in the episode "Abu el Banat") is Tonka.
President Bartlet mentions the phrase "street gang" while talking to Chief of Staff Leo McGarry. Martin Sheen, who portrays Bartlet, was part of code-named "PBR Street Gang" in his role in Apocalypse Now (1979).
Elisabeth Moss returns as Jed's daughter Zoey Bartlett. Mark Moses appears as Congressman Richter. Moss and Moses would later work together on Mad Men (2007) as co-workers and occasional lovers Peggy and Duck