FRANCE’S most pro-European presidential candidate took his campaign to London this week to a rapturous welcome. Emmanuel Macron, a 39-year-old former Socialist economy minister, was there to court the French vote abroad, and is exactly the sort of upbeat, international-minded tech enthusiast that London’s latte-drinking French voters adore. Campaigning as an independent for votes on the left and the right, Mr Macron has pulled off the astonishing feat of hauling himself up from rank outsider to joint second place in the polls. But the closer he gets to a shot at the French presidency, the tougher his campaign is turning out to be.

A few days before Mr Macron turned up in London, he had been in more hostile territory: the Mediterranean naval port of Toulon, traditionally held by the right. The entrance to his rally was blocked by scores of enraged National Front (FN) supporters and pieds-noirs (ethnic French who resided in Algeria during colonial rule), chanting “Macron traitor!” On a trip to Algeria that week, he had called France’s colonisation of the north African country a “crime against humanity”.

The rally went ahead all the same. Mr Macron told the audience that he was “sorry” if he had “wounded” anybody, but that France needed to confront all sides of its history. The venue was a little over half full, and the atmosphere flat. The crowd seemed motivated as much by curiosity as conviction. Jean-Luc, a high-school maths teacher, said he had never been to a political rally and was “intrigued” by Mr Macron. Robert, a retired salesman, said he voted for François Fillon, the centre-right candidate, at his party’s primary but was now “looking for a way out”. (Mr Fillon is under investigation for having employed family members on the parliamentary payroll, despite little evidence that they did much work.) It was Mr Macron’s “different way of doing politics” that appealed, said a retired naval worker and Socialist voter; he was not yet sure of his vote.

With two months to go before the first-round, the French presidential election has become more unpredictable than any in recent history. The only near-certainty is that the FN’s Marine Le Pen will win one of the two places in the run-off. This has turned the election into a race to face her. Though she has staged almost no rallies, Ms Le Pen tops first-round polling, with about 26% of the vote (see article). Over three-quarters of her voters say they are sure of their choice. For Mr Macron, who is neck-and-neck with Mr Fillon in second place, this share is just 45%.

That Mr Macron is in this position is remarkable enough. This, after all, is a young man who in July 2014, after quitting his job as deputy chief of staff to President François Hollande, could be found in his top-floor office at the Elysée Palace cheerfully mulling over plans to write a book, or perhaps teach philosophy. Today, the offices of En Marche!, the movement he founded last year, are filled with young people in sweatshirts, and feel like a cross between a start-up and a student society. He has attracted policy heavyweights, such as Jean Pisani-Ferry, an economist, and the support of François Bayrou, a centrist who has declined to run himself. And he is recruiting candidates from all backgrounds to stand at parliamentary elections in June. The objective, says Mr Macron, is to reject “yesterday’s choices”, pursue “radical novelty” in politics, and build “a new France”.

Not your regular Gilles

Yet, besides his inexperience, two obstacles in particular lie ahead if Mr Macron is to beat Mr Fillon into the second round. One is whether he can find a way to speak to a broader electorate, beyond the metropolitan voters with a university degree who favour him. “He’s too intellectual,” says a retired antique dealer, in a café overlooking the port in Toulon, where the aircraft carrier Charles de Gaulle is docked while undergoing repairs. Mr Macron’s overtly pro-European politics are unfashionable in parts of France these days. His support for Germany’s open-border policy towards Syrian refugees—he says it “saved our collective dignity”—collides with a popular mood of rising nationalism. And Mr Macron’s embrace of technological disruption does not resonate with those who fear they will be its next victims. “He is quite weak among manual workers and employees, and it’s not possible to construct a successful candidacy without them,” says Jérôme Fourquet of Ifop, a polling group.

The second is how far his poll success is down to an engaging personality rather than a convincing programme. The country, he says, needs “vision”, not scores of policy ideas that promptly get shelved by presidents in power. But his reluctance to be too precise has left Mr Macron open to the charge of ambiguity. Asked which of his policies they liked best, supporters questioned in Toulon were unable to answer. Mr Macron is due shortly to unveil more specific plans which, perhaps tactically, he has long avoided. Yet this carries fresh risks. Some of the ideas he sketched out in “Révolution”, the book he published last year, are profoundly radical, certainly for France. He wants to curb the overall level of public spending; have the state take over the employer- and union-run unemployment benefit system in place since the second world war; and devolve most negotiations on working conditions to companies. He is liberal, he says, “in a Nordic sense”. Getting the right balance between what France needs, and what the French will vote for, will be perilous.

A historically unusual opportunity is within Mr Macron’s grasp: the chance of beating all established party candidates into the second round, and from there into the presidency. Polls suggest that he would be a more solid run-off candidate against Ms Le Pen than would the damaged Mr Fillon. Under the Fifth Republic, no independent has ever pulled off such a feat. Then again, none has had such a remarkable opportunity to do so.