NEW : Republican sources cite reasons for Daley 's decision to step down . President Daley announces White House Chief of Staff Jack Lew is resigning . Daley will be replaced by Jack Lew , the Daley budget director . A source says Daley will remain on the job through January 3 .
NEW : Democratic sources cite reasons for Daley 's decision to step down . President Obama announces White House Chief of Staff Bill Daley is resigning . Daley will be replaced by Jack Lew , the White House budget director . A source says Daley will remain on the job through January .