Health and Human Services Secretary Tommy Thompson resigned Friday, broadening an exodus that has emptied more than half of President Bush's Cabinet before he starts his second term.
"It's time for me and my family to move on to the next chapter in our life," Thompson said at a news conference a few hours after giving his formal resignation to the president.
Thompson used the news conference to tout what he said was a long list of accomplishments in his tenure as head of a department that oversees a broad range of health-related issues — not once mentioning the political controversy that accompanied many of them.
"We touched the third rail of politics," he said, referring to the landmark Medicare legislation that passed Congress a little more than a year ago.
"We turned America's attention to disease prevention," he said. "And we're waging a bold new global fight against HIV AIDS." He also referred to the shortage of flu vaccine as well as his efforts to respond to the threat of anthrax.
Thompson had not yet stepped before the microphones when officials said Mark McClellan, the Medicare chief and brother of White House press secretary Scott McClellan, was Bush's likely choice to take over the sprawling HHS bureaucracy.
Thompson is the eighth member of Bush's 15-person first-term Cabinet to depart, and others are expected.
He said he intends to serve until Feb. 4 or until the Senate confirms his successor.
Thompson said at his news conference that his term as HHS secretary marked 40 years in public life. That included 14 years as governor of Wisconsin, where he gained national recognition for his work in overhauling the state's welfare program.
News of Thompson's departure came not long after Bush introduced former police commissioner Bernard Kerik as Tom Ridge's successor to be secretary of homeland security.
Kerik is the steady former military man who helped New York get back on its feet after the Sept. 11 terror attack.
"Bernie Kerik is one of the most accomplished and effective leaders of law enforcement in America," Bush said.
Kerik said what he witnessed in the days after the attacks would be etched in his mind if he were confirmed to lead the department. "I know what is at stake," Kerik said.
"Both the memory of those courageous souls and the horrors I saw inflicted upon our proud nation will serve as permanent reminders of the awesome responsibility you place in my charge," he said.
Bush also lost his ambassador to the United Nations, John Danforth, who is retiring.
Friday's ceremony has become a ritual as Bush rounds out his Cabinet for his second term. He stood in the Roosevelt Room with Kerik, as the nominee's wife and some of their children looked on.
Joe Allbaugh, the former FEMA director who was mentioned as a candidate for the job, said Kerik will "be drinking water from a fire hose for quite a while, but I know he's up to the challenge."
Former Mayor Rudolph Giuliani, Kerik's boss in city government and later at a private consulting firm, told the Associated Press the former undercover detective will surprise many within the sprawling bureaucracy of homeland security.
"When you see him, he's a big strong guy and a black belt," said Giuliani. "What you get to know when you work with him is how smart he is ... how effective and sophisticated a manager he is."
Rep. Christopher Cox, R-Calif., chairman of the House Homeland Security Committee, said "there is no doubt that Bernie is a strong, no-nonsense manager who is intimately familiar with the homeland security mission."
Sen. Susan Collins, R-Maine, chairwoman of the Senate Homeland Security and Governmental Affairs Committee, said her panel would conduct confirmation hearings as swiftly as possible, calling Kerik "a strong candidate."
Samuel J. Plumieri, superindent of the Port Authority police, which lost 37 of its own on Sept. 11, said his department had worked closely with Kerik.
"We are confident that he will be able to aggressively deal with the nation's security interests," Plumieri said.
A military policeman in South Korea in the 1970s, Kerik's first anti-terrorism work was as a paid private security worker in Saudi Arabia. He joined the New York Police Department in 1986, first walking a beat in Times Square when it was still a haven for small-time hustlers.
He eventually was tapped to lead the city's corrections department, and was appointed police commissioner in 2000.
It was in that position that he became known to the rest of the country, supervising the NYPD's response to the Sept. 11, 2001, terror attacks, often at the side of then-mayor Rudolph Giuliani. Kerik helped rally a department that lost 23 members and became a steady presence for a population deeply shaken by the attacks.
Kerik inherits a new and sprawling bureaucracy. The creation of the department in 2003 combined 22 disparate federal agencies with more than 180,000 employees and a combined budget of $36 billion. The organization is still learning to work together and faces criticism over aspects from the coordination of finances to computer systems.
Danforth had been mentioned as a possible successor to Secretary of State Colin Powell, but Bush picked Condoleezza Rice.