Officially, Europe's conservatives already have a candidate for the next president of the European Commission. But a potentially more palatable alternative is waiting in the wings.

Step forward Michel Barnier, the European Commission's chief Brexit negotiator, basking in the glowing praise of EU leaders who endorsed his deal with the U.K. on Sunday.

If Barnier becomes Commission president next year, he would be much more than Europe's top bureaucrat. When he ran for the post four years ago, he proposed the Commission should focus on "more politics and less regulation." More recently, he has called for the EU to cooperate more closely in trade, technology and defense to ensure it is a major player on the world stage. As Commission chief, he would also be the ultimate boss of the body negotiating a long-term trade deal with the U.K.

Barnier declined to run for the nomination of the European People's Party (EPP), the Continent's leading political force, this time around as he was still deep in the Brexit talks during the selection process. At a congress in Helsinki earlier this month, the EPP chose Manfred Weber, the German leader of its group in the European Parliament, to be its so-called Spitzenkandidat — lead candidate for next year's European Parliament election and nominee for Commission president.

But Weber has never held high executive office and a number of EU officials, diplomats and lawmakers doubt he will end up as Commission president. Barnier, by contrast, has served two terms as a European commissioner and held senior ministerial posts in his native France. He has also won plaudits from across the EU — and across political divides — for his work on Brexit, which has given him the perfect opportunity to deepen his network of political contacts around the Continent.

"All those who believe in Europe should stand behind Barnier" — Jean Arthuis, French liberal MEP

Current Commission President Jean-Claude Juncker led the tributes to Barnier after EU leaders backed the Brexit deal, noting he has maintained unity among the EU's 27 members despite great pressure. The leaders went as far as to thank Barnier for his "tireless contribution" in their official conclusions of the summit, while German Chancellor Angela Merkel hailed the Brexit deal as a "diplomatic masterpiece."

All of which means that Barnier is still being discussed in EU circles as a contender to take over the Commission after Juncker's term expires next year, even though he is not technically a candidate.

Barnier has repeatedly avoided commenting on his ambitions, insisting he is fully focused on Brexit. He declined to comment for this article. But earlier this month Barnier gave a speech entitled "Reweave the European flag," that went far beyond his Brexit remit to present a vision of Europe's future. In his letter declining to run for the EPP nomination, Barnier also appeared to leave the door open to taking another top post after his Brexit work.

"Of course, I shall remain committed in future and available to defend our values and renew together the European project," he said in a handwritten final paragraph.

Big obstacles

The Frenchman would need to overcome significant obstacles to make it into the top EU job but none of them seem insurmountable at this stage.

For one thing, installing Barnier as Commission president would be politically fraught. It would risk an institutional crisis between the leaders of EU countries, who propose the Commission chief, and the European Parliament, which has to approve the nomination. The legislature has declared it is ready to reject any nominee who did not run as a Spitzenkandidat in the election.

Brexit also carries an element of danger for Barnier. He has forged rare unity among EU members but he will be defined by the deal's success or failure. If it is rejected by the U.K. parliament, the EU will almost certainly blame Britain rather than its own point man. But, if some form of deal negotiated by Barnier ends up being ratified, the EU will have to consider whether it wants a frontman so closely associated with a venture whose long-term fortunes are uncertain, both for the bloc and for the U.K.

Another hurdle for Barnier is that he would need the backing of Emmanuel Macron. That would deprive the centrist French president of the chance to appoint a European commissioner from his own political party. (Each EU member country nominates one member of the European Commission.)

A senior official from a Southern European country said Barnier could become Commission president but noted bluntly: “Only if Macron wants it too.”

However, Barnier's decades-long commitment to the European project means he has supporters even among politicians from rival camps, particularly in France.

"All those who believe in Europe should stand behind Barnier," said Jean Arthuis, a French liberal who is close to Macron politically and heads the Budgets Committee in the European Parliament. "He has an excellent profile."

Marching behind Barnier?

Many members of Macron's La République En Marche party have viewed Barnier, who is 67, as an emblem of the old political establishment, unfit to embody the generational change they want to promote. Some En Marche officials have their sights set on Margrethe Vestager, the European commissioner for competition, as their dream candidate to lead the Commission.

But the Danish commissioner does not look to have the support of her national government and belongs to the liberal ALDE group, which is on course to come third in next year's election and would therefore not be in a strong position to claim the Commission presidency. The EPP, on the other hand, is almost certain to come first, putting it in pole position to secure the post — if not for Weber, then for another conservative.

"If there is an opportunity for Barnier to be the next president of the Commission, I don't see how France and Macron could refuse that," said an En Marche member of the French parliament.

The MP added that Barnier is Macron-compatible in that, although he is a member of the conservative Les Républicains, his views are closer to the party's centrist standard-bearer Alain Juppé than its current leader, right-winger Laurent Wauquiez.

Another factor that may count in Barnier's favor: He previously backed the French presidential ambitions of Bruno Le Maire, who is now France's powerful finance minister after switching from the center right to join Macron's En Marche.

In his speech on Europe's future to a conference of Belgian Catholics, Barnier called for Europeans to "reaffirm our sovereignty in major fields which would otherwise be the exclusive domain of continental states: trade, defense and digital.”

"Let's not be ashamed of Europe,” he declared.

Cross-party support

Under the Spitzenkandidat system first used in 2014 and backed by the biggest groups in Parliament, the next Commission president should be a lead candidate put forward by a pan-European party for the European election. But the next Parliament is likely to be more fragmented, putting a premium on a candidate who can build a broad, multiparty majority. Some on the political left say Weber will struggle to win backing from their camp whereas Barnier would fare better.

European leaders, meanwhile, have made clear they won't be bound by the Spitzenkandidat process, leaving open the possibility they could nominate someone else for the Commission presidency.

“Barnier wouldn’t cause any problem to either the left or the right,” said an official from the Socialists & Democrats group in the Parliament. “And nobody is going to cast any doubt on his pro-European commitment.”

"The next Parliament will be happy to give itself room for maneuver ... even the Parliament can’t be satisfied with two candidates like Weber and Timmermans" — S&D official

“When you look at what he did in his regional policy portfolio, he was very progressive,” the official added, referring to his time as the commissioner for regional policy and reform of European institutions.

The official spoke on condition of anonymity as Europe's Social Democrats have chosen Commission First Vice President Frans Timmermans as their Spitzenkandidat and nominee for Commission chief. But, the official said, neither the Dutchman nor Weber has sparked any great enthusiasm for their candidacies in the Parliament.

"The next Parliament will be happy to give itself room for maneuver ... even the Parliament can’t be satisfied with two candidates like Weber and Timmermans,” the official said.