Margrethe Vestager’s quest to succeed Jean-Claude Juncker as European Commission president kicks off on Thursday, but the EU’s high-profile competition chief risks falling at the first hurdle.

While Vestager’s battles against U.S. tech giants such as Google and Apple have won her wide support in Brussels — and make her the female superstar candidate in Europe’s liberal camp — her immediate problem is that her home country of Denmark looks unlikely to nominate her for a top Commission post.

On Thursday, Europe’s liberal ALDE group is set to name Vestager among its seven leading candidates for May’s European election, only a day after she rolled out her third heavy antitrust fine against Google. While these seven big hitters in ALDE’s “Team Europe” are technically only the party’s top picks to enter the European Parliament, they are actually the prime candidates for a raft of more senior EU jobs, including Commission president.

To replace Juncker or even stay on as a senior commissioner, however, Vestager faces a daunting obstacle course. The liberals are on track to be only the third biggest political grouping in the EU and Vestager hails from a non-eurozone country. Even if an impending Danish election miraculously plays to her favor, she still faces the problem of French President Emmanuel Macron, who is expected to be Europe’s liberal kingmaker. People from his La République En Marche party say his enthusiasm toward her has cooled in recent months.

Over her final few months as commissioner, she still has a few trump cards she can play to raise her political profile — including potentially opening a landmark antitrust case against Amazon and fining top German carmakers in a high-profile cartel probe — but these moves could count for nothing if her candidacy falls flat in Copenhagen and Paris.

"After the Siemens-Alstom merger, supporting her is going to be complicated" — En Marche official

Two years ago, speculation was rife in Brussels that Macron saw Vestager as a kindred spirit and would seek to maneuver her into the EU’s top job. As a woman and a free-marketeer, she was seen as a welcome breath of fresh air in Brussels.

Jean Arthuis, a member of the European Parliament from En Marche, stressed that the Dane was a “remarkable personality” and praised her for taking on big corporations such as Apple and Amazon over their tax avoidance strategies in Europe. “She was eager to put the tax issue on the table and that was very positive,” he said.

Trouble ahead

Arthuis noted, however, that Vestager’s relationship with France had cooled lately. The chief problem was Vestager’s decision to block a mega-merger in the rail sector between France’s Alstom and Germany’s Siemens. Paris insisted a European train-building champion was required to challenge China, but Vestager argued the deal would ramp up prices for European consumers.

“We must go further and combine liberalism and protectionism,” Arthuis said. “Otherwise China is going to eat us all up.”

Another En Marche official was even more circumspect about Vestager’s prospects: “She’s a very brave commissioner, the first one to apply fines to industrial giants,” the official said. “But after the Siemens-Alstom merger, supporting her is going to be complicated.”

Vestager on Wednesday flatly declined to answer a question about her prospects of succeeding Juncker, well aware that her problems start at home. Denmark’s Prime Minister Lars Løkke Rasmussen, despite being part of the same European liberal family, is a political opponent and is supported in parliament by the anti-immigration Danish People’s Party, which is categorical that Vestager should not be Copenhagen’s nominee. “She wants more EU and less Denmark. We want the opposite!" DPP leader Kristian Thulesen Dahl tweeted last month.

Kasper Møller Hansen, a political scientist at the University of Copenhagen, said: “It seems difficult to see why [Rasmussen's] Liberal Party should reappoint her when they have their own candidates. I am sure there are people in and around the party who think they are up to the job.”

Danish politics are fluid because an election must be held before June 17, and polls suggest that the center-left Social Democrats, which are allied to Vestager’s Radikale Venstre party, hold a narrow lead over Rasmussen’s bloc. A survey by Gallup from mid-March put the center-left at 51.2 percent versus 48.8 percent for the center-right.

Still, a Social Democrat win does not necessarily help Vestager either, as that larger party will be likely to promote its own candidates. As a finance minister in Denmark, she was seen as tough on unions.

Analysts noted than Social Democrat leader Mette Frederiksen was liable to look to leading players in her own team.

Rune Stubager, a political scientist at Aarhus University, said: “It could be Dan Jørgensen, former MEP and minister, current MP and part of the party leadership. It could also be Nicolai Wammen, former minister, current MP and part of the leadership.”

Still, Møller Hansen from the University of Copenhagen held out a glimmer of hope for Vestager's supporters. If it was clear that she really was headed to be the next Juncker, that could force a compromise.

“If the role of head of the commission is really in play then she might be put forward."

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