A man who rose to fame using the catchphrase “you’re fired” now faces the gargantuan task of assembling a presidential administration capable of running the most powerful nation in the world.

And that involves hiring people. A lot of people.

According to the Partnership for Public Service, a nonpartisan and nonprofit organization that began working with both major party nominees earlier this year to help prepare the eventual winner to begin the transition process, the incoming administration will be charged with filling the jobs of as many as about 4,000 political appointees.

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That's a heavy lift for any new administration, and a particularly daunting one for a president-elect who was reportedly surprised to find out after winning the election that he would have to replace the White House staff at the end of President Barack Obama's term.

And while the president-elect has wide authority to select several hundred incoming members of the White House staff — like his chief advisers and communications teams — more than 1,000 incoming appointees must be confirmed by the United States Senate. That includes big-name posts like the heads of the Defense, State and Justice Departments, but also a host of assistant and deputy secretaries, cabinet advisers and ambassadors.

“It’s just a very, very complicated task, particularly when you get outside the White House staff,” said Mark Abramson, the president of Leadership Inc. and an expert on government executive management.

The new administration must also assemble an infrastructure capable of selecting the armies of policy professionals, lawyers, scientists, schedulers, speechwriters and press secretaries who populate each federal agency. Beyond White House staffers and positions requiring Senate approval, there are also more than 2,000 political appointees included in the leadership of the engines of government, from the USDA to the Justice Department to NASA.

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Incoming Cabinet secretaries may want to fill those jobs with their own loyalists, but may also face pressure from the White House to select or discard certain applicants. In many cases, they may end up leaning for months on career professionals already familiar with the jobs as they assemble their personalized teams. Meanwhile, Trump has proposed a hiring freeze for many federal employees, aimed at ultimately reducing the size of the federal government through attrition.

A huge initial challenge for applicants to jobs requiring a greenlight from the Senate will be vetting, a task for which many — perhaps most — potential contenders may be unprepared.

“If you’re going to get a Senate appointment, you have to get financial clearances, security clearances, FBI field investigations,” said Abramson, who added that such background research can be particularly lengthy for candidates without significant previous experience in government.

“There’s a lot of pieces to the puzzle and there’s an enormous amount of applicants," he added. "It’s going to take a long time to get sorted out.”