Martin Sheen President Josiah "Jed" Bartlet Actor Stockard Channing Abigail "Abbey" Bartlet Actor John Spencer Chief of Staff Leo McGarry Actor Bradley Whitford Dep. Chief of Staff Josh Lyman Actor Allison Janney Press Secretary Claudia Jean "C.J." Cregg Actor Richard Schiff Communications Dir. Toby Ziegler Actor Dulé Hill Charlie Young Actor Janel Moloney Donna Moss Actor Joshua Malina Will Bailey Actor Mary McCormack Kate Harper Actor Rob Lowe Sam Seaborn Guest Star Alan Alda Senator Arnold Vinick Guest Star Kristin Chenoweth Annabeth Schott Guest Star Jimmy Smits Matthew Santos Guest Star Teri Polo Helen Santos Guest Star Lily Tomlin Deborah Fiderer Guest Star NiCole Robinson Margaret Guest Star Kim Webster Ginger Guest Star Michael O'Neill Secret Service Agent Ron Butterfield Guest Star Allison Smith Mallory O'Brien Guest Star Matthew Del Negro Bram Howard Guest Star Karis Campbell Ronna Guest Star Peter James Smith Ed Guest Star Renee Estevez Nancy Guest Star John Wells Executive Producer Christopher Misiano Director Aaron Sorkin Writer Debora Cahn Producer Lawrence O'Donnell Executive Producer