No matter who inherits 1600 Pennsylvania Avenue after November 6, one question will continue to exercise Washington's breathless commentariat: will Hillary Clinton run for the White House in 2016?

The indecent haste and seeming irrelevance of that suggestion – just over a week from the present presidential poll – have done nothing to halt impatient tongues in a suddenly too-close-to-call campaign. But underlying such speculation there is also this troublesome teaser: would Secretary of State Clinton have made a more effective Commander in Chief than the candidate who, after that bitter fight for the Democratic nomination, won the job in 2008?

By most informed accounts, Mrs Clinton will take a break from political life when a new administration swings into action next January, and although a perilously fractured world has allowed her no summit triumphs in the Middle East or peace settlement in Afghanistan, she will still leave the state department with her reputation enhanced. Recently The New York Times hailed her as a "rock star diplomat" while other seasoned Washington watchers have assessed her record as significantly more distinguished than that of predecessors such as Warren Christopher, Madeleine Albright, Condoleezza Rice and Colin Powell.

That, of course, was before Mrs Clinton took political responsibility for the security lapse involved in the terrorist attack on the US consulate in Libya, which killed ambassador Chris Stevens and three staff in September. But even this admission is seen to her credit; a selfless attempt to protect Barack Obama against his Republican rival Mitt Romney's hawkish charge that the Benghazi tragedy emphasised the President's weakness on foreign policy.

Yet would this former, pro-active First Lady and former New York senator really have made a better fist of the presidency than Mr Obama whose tenure, according to supporters and detractors alike, has been damaged by dithering? A funny business, politics: who would have guessed that even some Republicans now look back on the two-term Clinton presidency as "those good old days" of rapid growth, low inflation, low unemployment and decreased poverty. President Obama, by contrast, is condemned for poor performance on job creation, although the comparison is unfair – he has, after all, struggled against unprecedented banking chicanery and a global recession. But there are those who believe Hillary, with irrepressible Bill in the wings, would have brought more vision and clout to the present problems crippling America.

An over-scrutinised public life has taught Mrs Clinton to remain inscrutable about her private intentions, so the question of whether she will run for the highest office in 2016, at the age of 68, is left to speculation. What she does concede, though, is the punishing wear-and-tear of her present role: she is exhausted. But a four-year sabbatical would allow her to recoup her energy while laying the groundwork for Oval Office occupation. When she rejected the offer of Vice Presidency in 2008 was she casting a shrewder eye to the long view? Only rarely does a White House number two become its Numero Uno, but the Secretary of State job confers a status beyond party politics. In Mrs Clinton's case it has shielded her from the electorate's seething anger about the country's paralysed economy.

Meanwhile Bill Clinton, overcoming his hostility towards Mr Obama for "snatching" the Democratic nomination from his wife, has swung his considerable weight behind the President's campaign. As a result the former 42nd US President is enjoying an Indian summer, reminding America that, at 66, he remains a class act. A consummate politician intellectually ahead of the game and a charismatic communicator, should Hillary commit herself to the 2016 race? Bill, constitutionally prevented from seeking a third term, would be her most formidable champion.

If Benghazi is the notable blot on her time as Secretary of State, what is widely admired is her loyalty to Mr Obama and the loyalty she commands from her own staff whose morale was in tatters under George W Bush's administration. And with the help of Bill, the flawed but gifted charmer, she could certainly pull in the women's vote more readily than the Republican party. So, would it be a Vote One, Get Two presidency all over again. No-one should underestimate the chutzpah of the Comeback Couple.