After Santos wins, Donna Moss becomes chief of staff to whom?

After Santos wins, Donna Moss becomes chief of staff to the First Lady.

Donna Moss spends most of The West Wing as Josh Lyman’s senior assistant, but her ambitions expand during the later seasons. She leaves the White House to work for Bob Russell’s presidential campaign and then joins Matt Santos’s campaign as a spokeswoman.

After Santos wins the general election, Donna receives a senior role in the incoming administration: chief of staff to the First Lady, Helen Santos. The position reflects her growing political experience and her movement beyond the assistant role that defined her early years on the show.

Viewers sometimes confuse Donna’s new job with the White House chief of staff position. That office goes to Josh Lyman after Santos’s election. Donna’s title is specifically tied to the First Lady’s office, while Annabeth Schott becomes press secretary to the incoming First Lady.