John McCain's campaign manager and chief strategist are gone from their leadership roles, according to two officials with knowledge of the staff changes.
One official said Terry Nelson resigned as campaign manager for the Republican presidential candidate and John Weaver stepped down from his post of chief strategist on Tuesday. But another official said Nelson was fired.
The officials spoke on the condition of anonimity because the shake-up has not been made public.
Two officials said Rick Davis, a longtime aide to McCain, will take over the campaign.
UPDATE: Marc Ambinder reports that Mark Salter is also leaving the campaign.
Republicans close to the campaign say that Mark Salter, McCain's long-time chief of staff and co-author of his five books, is also leaving the campaign.
The sources said that the three did not split from McCain amicably.