The appearance of the first formal candidate in the EU top jobs derby on Friday clarified little about who will run the place a year from now.

But the surprise entry of Manfred Weber — a Bavarian politician without much relevant job experience or name recognition outside Brussels — brought home one salient reality about the campaign now taking shape: Coalition-building, more than the outcome of European parliamentary elections or the preferences of powerful EU leaders, is what now matters.

There are a couple of reasons for this changed dynamic. No political group, including Weber's once dominant center-right European People's Party, polls over 30 percent, heralding a messy outcome in next spring's poll. Euroskeptics are on the rise, giving establishment groups more reason to join forces. And no one agrees on precisely how the Commission presidency that Weber wants — or the other open seats atop the European Council, the European Central Bank or the EU's diplomatic service — will be filled, making it easier to improvise.

As a result, Europe looks to be headed for something resembling an American brokered convention, or make that an Arabic souk, where backroom haggling will be decisive. On current vote projections, it'll likely take at least three parties to join forces to win the Parliament’s support for a new Commission president. “There’s going to have to be some kind of coalition government, coalition Commission after the election,” said an official at the headquarters of Weber’s EPP.

And when the dust settles and Weber or someone else has their feet under the 13th floor desk in the Berlaymont building, it'll be time for whatever coalition got them there to move on to decide on the other EU jobs up for grabs in 2019, starting with the presidency of the European Council.

Handicapping Weber

By securing the support of Germany's Chancellor Angela Merkel to be the party's Spitzenkandidat — favored candidate — for Commission president, Weber does have the inside track to win the nod at the EPP's Helsinki congress in November. Other candidates lurk, including Brexit negotiator Michel Barnier and former Finnish Prime Minister Alexander Stubb, who could still trip him up.

Whoever comes out ahead in Helsinki would, in the previous election cycle in 2014, have felt confident about getting the Commission presidency. Under the Spitzenkandidat system, the candidate from the political family that gets the most seats in the European Parliament election is supposed to be endorsed by EU leaders. The EPP remains the most likely leading vote-winner.

But there's a different script getting prepared for 2019. Liberal and Socialist strategists say the EPP, for 20 years the biggest party in the European Parliament and around the EU summit table, can no longer dictate the terms of European deal-making.

The EPP is down to eight seats out of 28 in the European Council. According to aggregated national opinion polling, it's on track to win 185-190 seats out of 705 (the new total once the U.K. is gone, down from 751) in the 2019 Parliament election. That’s down from 217 today, and 277 as recently as 2009.

Despite the center right's declining fortunes, Liberals and Socialists freely admit they can’t beat the EPP. They're bracing for the give-and-take negotiations likely to take place after the election.

“The Liberals can’t, on their own, undermine the process, but Macron can" — EPP official

If he does get the EPP nomination, Weber has a couple of advantages that he will leverage to insist on first dibs on the Commission presidency: He's from the biggest party in the biggest country and belongs to the largest EU-wide political family. In the words of one Liberal strategist: “The reason that they [the EPP] cling onto the Spitzenkandidat so desperately is because that’s basically the only way for them to 'secure' the European Commission position.”

But Weber has evident shortcomings. He's never served as a prime minister, as have the previous four holders of the office, and he has no executive government experience. He's from Merkel's sister Bavarian party, and not a close confidante. His German passport will rankle other EU countries. All that makes him more dispensable than a bigger name candidate.

The Spitzenkandidat system has only been used once before, and EU leaders haven't fully committed to it. In 2014, Martin Selmayr, now the Commission’s secretary-general and then Juncker’s campaign chief, was able to corner Merkel into agreeing to a Juncker-led Commission — insisting it would be undemocratic for EU leaders to choose someone other than Juncker for the job, since the EPP placed first in the election and he was its candidate. It'll be harder to make this argument stick a second time around, especially if the candidate is Weber (a Bavarian MEP) rather than Juncker (who led a country for the best part of two decades).

Macron factor

Weber's relatively weak position isn't lost on the other political groups.

In a bid to strengthen their hand, the Liberals are looking to France's President Emmanuel Macron. He hasn't joined a European political family and will likely only play the Spitzenkandidat game if he can win it.

“To get 353 [just over half the seats in the European Parliament] you need at least two parties and probably three. If the smaller party has more prime ministers in the Council they still might be able to claim the Commission president,” said one official from the Alliance of Liberals and Democrats for Europe.

It’s a hopeful view: ALDE has seven heads of government but they represent just 10 percent of Europe’s population. Even adding Macron to the mix would only take that latter figure up to 24 percent.

The EPP is, however, aware that Macron can spoil its Commission chances, and the best way to prevent this is for Merkel and Macron to strike a coalition deal.

“The Liberals can’t, on their own, undermine the process, but Macron can. If he’s agreed a division of jobs with Merkel, he has no reason to undermine the process,” the official at EPP HQ said. “His interest is to support the process to make sure he gets the ECB for France.”

Beware the populists

The populists could throw a spanner in all these calculations. The Parliament’s combined Euroskeptic forces are on track to win around 150 seats in the election, and some predict as many as 200. If they unite behind a single Spitzenkandidat or under one political umbrella — something they’ve never managed before — they could challenge the EPP for first place in the chamber.

Euroskeptics beating the EPP would spark a constitutional crisis that could force the member countries and Parliament to scrap the Spitzenkandidat process altogether or choose someone from a party that didn't come first.

More likely, a Euroskeptic boom would push the mainstream to work together and divide the spoils of EU top jobs. In that scenario it’s easier to see Weber being given the presidency of the Parliament rather than the Commission.

Whatever the route, the destination appears the same: a messy coalition-building process in 2019. “A deal can be made,” said the EPP HQ official. “And it would be a good message for Brussels to send to the world if it can be made. A serious, multi-party dream team. That’s a good narrative, and it’s safe.”