Whoa. So not only is Martin Sheen in
"The American President", but so is
Joshua Malina (aka Will Bailey on "The West Wing") AND
Anna Deveare Smith (aka Nancy McNally, kick ass women defense advisor on "The West Wing").
Uncanny? Yes.
EDIT: And let's not forget
"Nina Siemaszko", who played daughter Ellie Bartlett on TWW. Craziness!