Is this Portillo's swansong?

A fleet of black taxis was discharging guests outside Michael Portillo's elegant terraced house, a stone's throw from Buckingham Palace, for one of his regular summer parties. The guests who poured in to consume chilled wine and canap?s were a cosmopolitan array of television producers, friends from the City and tieless executives from the arts world.

Conspicuously, there were hardly any politicians. The only token reminders of the host's career as a Cabinet minister and would-be Conservative leader were grandees Cecil Parkinson and Ken Baker, and former campaign manager Francis Maude. In previous years, the guest lists for the Portillo summer soirees were markedly different. Not only did the quiet Belgravia square purr to the sound of ministerial limousines, the patio garden hummed to the voices of young, mainly Oxbridge - and all nakedly ambitious - political wannabes and cheerleaders from the press.

This year, there was no place for the Portillistas at their hero's home. Instead, he hosted what was in effect a networking event for the latest incarnation of Michael Portillo: television presenter, writer and friend of the arts.

Back at Westminster, the Portillo political legacy has withered over the past year. At Conservative headquarters, his name is now used as a term of abuse in the bitter fratricide between traditionalists and reformers. So unpopular has he become in his own party, even the modernisers around Iain Duncan Smith take pains to argue that their ideas are distinctly different from those of the one-time leadership frontrunner.

The former defence secretary, meanwhile, throws all his drive and intellect, the very qualities which launched his political appeal, into forging a new career as a TV personality. Had he left the Commons at the 2001 election, that might be expected. But Mr Portillo remains the MP for Kensington and Chelsea, one of the most desirable seats in the country for any Conservative. Despite a dwindling voting record and sub-zero profile at the House, he seems understandably reluctant to give up such a safe and convenient berth.

Now, however, Mr Portillo suddenly finds himself at a career crossroads, which is forcing him to decide once and for all whether to cut his remaining ties to the political world to pursue the chance of one of the most prestigious posts in the arts: the chairmanship of the Royal Opera House.

Reports last weekend claimed the MP, who was proposed for the job by Culture Secretary Tessa Jowell and thus by implication Tony Blair, had been ruled out by board members on the grounds that he would be too controversial a choice. One reason for him being blackballed, it was mooted, was lingering enmity over arts funding cuts during the Eighties, when he was regarded as Margaret Thatcher's favourite son.

The account was inaccurate in one respect, according to Covent Garden insiders. Although the Wagner-loving Mr Portillo would undoubtedly relish the job and is being encouraged by ROH executive director Tony Hall, he has so far refused to send in an application and, as a result, his name has not been formally considered.

What seems to have held him back is the stipulation laid down by board members that he would have to be willing to resign from Kensington and Chelsea to take up the job, a move which would finally sever his umbilical relationship with the Tories.

"He'd be bloody good because we need someone who knows how to cut a swathe through the various turf arguments on the board," said one senior supporter at the ROH. "Someone who can make a case with Government when we need to - and help push things through."

The ROH also desperately needs a figurehead who can navigate the funding maze which, under New Labour, increasingly puts a premium on arts bodies showing a strong social and educational commitment, while building up its identity as a London treasure rather than the preserve of the privileged. Mr Portillo, say his allies, could master the system and deliver the financial security the opera house craves. As a former treasury chief secretary, he might even persuade Covent Garden to balance its books.

He has some unlikely supporters, including Amanda Platell, the Tories' former director of communications who fought bitterly with him when they both served under William Hague.

"He is immensely qualified for the job," she said. "He not only loves music and opera, and knows a lot about it, he is an internationally known figure who knows how to run a complicated organisation.

"What more could the Royal Opera House want? The idea that he is being held back by the political decisions of the Thatcher government 20 years ago is, if true, disgraceful. It is time the arts woke up and started to appoint Tories to their boards."

Crucially, it is not too late for Mr Portillo to change his mind and submit an application. At Conservative Central Office expectations are so high that he will leave Westminster at the next election or before, a vulture-like flock of would-be successors have begun buttering up worthies in his constituency, in preparation for a selection contest.

But allies at Westminster say Mr Portillo is putting out confusing signals about how he intends to resolve the dilemma, leaving them baffled as to what he will do. On one hand, he refuses to quit his seat, while on the other leaving his former disciples in the cold.

One supporter who was among the inner circle of his leadership campaign - and like others was excluded from his summer parties this year - said there was resentment that their former leader had abandoned them. "He has left a lot of people homeless who would have died for him in the ditch," he said. "It is as if he is in denial that he ever was a Conservative politician."

Being an MP has helped rather than hindered his attempt to break into showbusiness, which may be another reason why Westminster is so hard to give up. "It makes him a more interesting, more bankable TV personality," said a former ally.

All three of the programmes he has completed this year owed their commissioning to his status as a political celebrity. Portillo in Euroland, shown in July, was a personal tour of the European Union from his eurosceptic viewpoint. Then there was Dinner With Portillo, on digital channel BBC4, in which he hosted a mock dinner party with politicians and pundits debating, inevitably, the euro. He was also invited to indulge another personal passion by making a documentary about Wagner's Ring, a musical work which he and his wife, Carolyn Eadie, travel the world to see performed.

"If I weren't Michael Portillo, obviously I wouldn't have been invited to make a film about Wagner," he once said, candidly.

There is now talk of collaborating with Labour's Mo Mowlam for a series in which they would do menial jobs in hospitals or jails, as a more "accessible" way of analysing political issues. It is the idea of Sian Kevill, the head of the BBC's New Politics Initiative unit, tasked with coming up with new ideas to pep up the corporation's current affairs output.

And there's the rub. As a Westminster personality, Michael Portillo can sell his services to an eager market of current affairs shows and programme-makers looking for a quirky amateur frontman. As a chairman of the Royal Opera House, committed to impartiality, political topics would be forbidden and the range of opportunities greatly limited. All the signs are that Mr Portillo is locked into an intoxicating love affair with the camera. Those who have worked with him on programmes say he has a natural talent for talking on screen and an eagerness to please. Once, he walked into a restaurant five times so that the final shot would be exactly right.

As a minister, Mr Portillo was always a Jekyll and Hyde character, exhibiting a haughty grandeur in public but in private charming his intimates with an attractive enthusiasm. In television, the latter side to his character is the only one on display. "He is a thorough professional and a pleasure to work with," said one of his new colleagues. "He does all his pieces to camera off the top of his head without a script. He takes a few minutes to think what he is going to say, during which nobody interrupts, and then he comes straight out with a seamless piece, delivered in vivid, accessible language."

Last week, he took a parttime directorship at BAE Systems, but it was generally seen as a smallscale job to subsidise his other interests rather than the start of a collection of boardroom seats. It is startling that this is the same man who came within a single vote of going through to the final shortlist in last year's Tory leadership election - and would probably have then won against Ken Clarke to become leader of the Opposition.

His well publicised admission that he had youthful homosexual experiences was not, however, what stopped him. Friends and allies agree that Mr Portillo, while going through the motions of campaigning, did not want to win. By refusing to compromise on his most controversial views, including gay equality, he effectively - and probably deliberately - frightened away supporters.

"At the morning meetings he just showed no interest," said one campaign team member. "He had had enough of the unpleasantness of frontline politics and wanted to bow out. The sad thing is he took a lot of people with him on his personal journey to reach that decision, then he walked away."

Today, the most wounding charge levelled at Iain Duncan Smith's advisers by critics like Lord Tebbit is that they are "those people surrounding Portillo". In truth, only a handful of his former army are still in regular touch - by his choice, not theirs. "Michael would say that this is a good thing, because it has been at least a year since anyone wrote a piece saying he was plotting to oust the party leader," said a friend. "That's what bedevilled him and broke his spirit."

Nobody at Westminster now thinks there is even a remote chance of another Portillo leadership bandwagon. "It will take seven years and another election defeat for the party to be ready again, and that's just too long," said a supporter, sadly.

Archie Norman, one of the campaign team who now runs the Cchange think tank, launched to keep the Portillo agenda alive, believes Mr Portillo has helped save his ideas by stepping aside. "It's true that his presence and personality overshadowed the reformist agenda," he said.

The jury is still out on whether Mr Portillo will stay an MP for the party which rejected him. But in his own head, this most sensitive and driven of politicians has already moved on.