Rahm Emanuel, President Barack Obama's chief of staff, will leave the White House today to launch a bid to become the mayor of Chicago.
"It's an emotional day for Rahm," an official told ABC News.
White House senior adviser Pete Rouse, who served as chief of staff to then-Sen. Obama, is expected to become interim chief of staff, although the White House has not officially confirmed the news.
Obama is expected to announce the staff change this morning at the White House.
"[Emanuel] has been the energetic, inspirational leader of us, taking the president's promises and agenda and enacting them into law," White House Press Secretary Robert Gibbs said Wednesday.
But Emanuel has also generated his share of controversy, angering many in the Democratic base and drawing fire from former Alaska Gov. Sarah Palin for his use of the word "retarded."
Emanuel's replacement, Rouse, is a longtime Washington insider who has a much lower profile than his predecessor.
Emanuel's departure comes amid a broad overhaul of the White House staff less than two years after Obama took office.
Our question to you today: Is Rahm Emanuel's departure good or bad for the Obama White House?