information:extraction, stylistic:tone
Succession

When Johnson assumed office, he asked the existing Cabinet to remain in place. Despite his notoriously poor relationship with Johnson, Robert F. Kennedy stayed on as Attorney General until September 1964, when he resigned to run for the U.S. Senate. Four of the Kennedy cabinet members Johnson inherited—Secretary of State Dean Rusk, Secretary of the Interior Stewart Udall, Secretary of Agriculture Orville L. Freeman, and Secretary of Labor W. Willard Wirtz —served until the end of Johnson's presidency. Other Kennedy holdovers, including Secretary of Defense Robert McNamara, left office during Johnson's tenure. Although Johnson had no official chief of staff, Walter Jenkins presided over daily operations at the White House. George Reedy, who was Johnson's second-longest-serving aide, assumed the post of press secretary when John F. Kennedy's own Pierre Salinger left that post in March 1964. Horace Busby served primarily as a speechwriter and political analyst. Bill Moyers handled scheduling and speechwriting part-time.