His job, the Mayor said, is to “say no.” It’s not easy “when people scream at you at a parade, give you the finger, criticize you in the paper.” Photograph by Pari Dukovic

Michael Bloomberg, whose third and final term as mayor of New York expires at midnight on December 31st, keeps a digital clock running in reverse in his City Hall office, counting down the days, hours, minutes, and seconds left in his term. He remains one of the wealthiest men in the city—his fortune is estimated at twenty-seven billion dollars—but this seems of limited comfort to him. In 2008 and 2012, he considered running for President, as a moderate Republican or as a self-financed third-party candidate, but he was eventually persuaded that he couldn’t win. Now he is clearly vexed by the challenges of envisaging his own future and a City Hall without him.

Bloomberg is seventy-one and conspicuously vigorous. He does not intend to retire. Yet he has told friends that he does not know what he will do next. “I can tell you what I want to do,” he said to me in late July. We sat at a tiny conference table in a cavernous office on the second floor of City Hall, which he shares with fifty members of his staff. He had taken off his charcoal suit jacket. “I haven’t had a vacation in twelve years,” he said. He imagined a week of skiing and a week of golf. “After that, I’d go ballistic.”

Bloomberg does not plan to return to running his business, Bloomberg L.P. Kevin Sheekey, who has been one of the Mayor’s top political strategists for the past twelve years, said that he expects Bloomberg to go through a sort of “re-start,” as he did when he left Wall Street, in 1981, and when he entered politics, in 2001.

Bloomberg has pledged to give away most of his fortune before he dies. That effort is under way. In 2011, the Chronicle of Philanthropy reported, Bloomberg donated more money to charity than all but four other Americans: Margaret A. Cargill, William S. Dietrich II, Paul Allen, and George Soros. He has a foundation, which every year gives away several hundred million dollars to a range of causes, with an emphasis on public health, government innovation, the environment, education, and the arts. The foundation has pledged a hundred million dollars to the Global Polio Eradication Initiative; six hundred million to combat smoking overseas; fifty million to support family planning; and another fifty million to the Sierra Club’s drive to reduce the nation’s reliance on coal plants. Bloomberg himself has reportedly given three million dollars to help establish Mayors Against Illegal Guns—one of many contributions he has made to advance gun-control laws—and $1.1 billion to his alma mater, Johns Hopkins University. Nevertheless, he said, “I don’t see myself as a full-time philanthropist.”

He also has invested in politicians outside New York. In July, he hosted fund-raisers for Mayor Cory Booker, of Newark, who last week won the Democratic nomination for U.S. senator from New Jersey, and Senator Joe Manchin, a West Virginia Democrat, who is running for reëlection. He has endorsed the bid by William Daley, President Obama’s former chief of staff, to unseat the Democratic governor of Illinois, and has spent considerable sums to try to defeat several Democratic and Republican senators and congressmen who have opposed gun control. Critics from both parties have complained about what they see as Bloomberg’s desire to become the nanny to citizens of other states. When Democratic Party leaders caution Bloomberg that defeating pro-gun Democrats might only result in wins for Republican allies of the National Rifle Association, he is unmoved. “You can’t have it both ways,” he said. “If you want to push an agenda that tries to keep guns out of the hands of criminals and people with psychiatric problems, the political party shouldn’t matter.”

I asked Bloomberg if he could imagine joining the President’s Cabinet. In theory, he said, “it would be fascinating to be Secretary of State, Secretary of Defense, jobs like that. Secretary of the Treasury, you want someone who’s a real economist”—and someone “who is maybe less opinionated.” Bloomberg thinks of himself as a team player, as long as it’s his team.

It is hard to imagine the endeavor that would sufficiently command Bloomberg’s restless ambition and vanity. He is an outsized character: the biggest plutocrat in a plutocratic capital, a creature of Wall Street who, flagrantly and legally, tapped his limitless bank account to become, and remain, mayor. Seeking a third term required him to ask the City Council to amend the City Charter on his behalf, about which he is unapologetic. “I can tell you that when it came to a third term the City Council majority thought it was good to change” the charter, he said. “And the public elected me.”

In private and in his natural social milieu, in the town houses and penthouses of the Upper East Side and Central Park West, Bloomberg is voluble, self-absorbed, brilliant. At dinner parties, while drinking copious amounts of wine, he makes plain his contempt for the New York Times, the media property friends say that he covets but most likely cannot own, and for President Obama, who occupies the office he craves but will never achieve.

“I am sympathetic that he has a Congress that is partisan,” Bloomberg told me, speaking of Obama. “In the past two hundred and thirty-five years, we’ve probably had lots of partisan Congresses. His job is to try to bring the parties together. And when he works at it he has actually done some pretty good things.” But he faults Obama for failing to invite members of Congress to join him on his regular rounds of golf, for instance, and for delegating to Congress the drafting of important regulatory legislation, such as the Dodd-Frank bill and the health-care law. “His job is to lead,” Bloomberg said. “He is the Chief Executive. It’s a separate but not an equal branch of government.”

Bloomberg has no complaints about his own leadership. He told me that he would like to be remembered as a mayor who brought the city “efficient, honest government that is responsive to the needs of the people, without worrying about politics, focussing instead on the things that will make a difference in the long term.”

In early September of 2001, Bloomberg was just another struggling candidate for mayor. A former Wall Street trader and aspiring media mogul, he possessed sufficient wealth and self-regard to think that his executive experience qualified him to run. He couldn’t run as a Democrat: the Party was overflowing with candidates, all united in their opposition to Rudolph Giuliani, the outgoing Republican mayor, whom Bloomberg respected.

During Giuliani’s two terms in office, New York’s crime rate, which had risen steeply through the nineteen-seventies and nineteen-eighties, went down, but his get-tough persona was wearing thin on the citizenry. The City Charter did not permit him to seek a third term, and polls suggested that, if he had, almost sixty per cent of the voters would have rejected him. Bloomberg realized that, by combining his millions with the Republican Party’s desperate desire to hold on to City Hall, he could be the Party’s savior. But, despite his financial largesse, he was an asterisk in the polls—an awkward candidate and a poor public speaker, whose view of Coney Island was from his private plane.