WASHINGTON — Efforts to form a second Donald Trump administration are already underway just days after his successful election as president, with speculation growing that he will bring back many people he worked with in his first administration to serve in key roles.

Following the choice of Susie Wiles, his senior campaign manager, to be the first female White House chief of staff, Trump has also tasked Robert Wilkie, his former secretary of veterans affairs, to lead the landing team at the Department of Defense. Brian Hook, a former director of the policy planning staff at the State Department, is leading the landing team there.