Merkel: Voters elect next commission chief 'in principle'

"A clear qualitative improvement is that, in principle, the Commission president gets elected," she said.

This represents a slight change in Merkel's stance.

She was never a fan of the idea that one of the six top candidates put forward by the main political parties in the European Parliament would become commission president after the EU vote.

The chancellor has in the past noted that the treaty only says that EU leaders must take the results of the election into account when making a nomination for the post, and that there is "no automaticity" between top candidates and the election result.

But after a weeks of pan-European campaigning and nine TV debates, the 'Spitzenkandidaten' are a reality leaders are finding more difficult to ignore.

According to one EU diplomat, "the fact that we have top candidates has created certain dynamics".

The threat of an institutional blockage is a possibility, with the European Parliament able to veto the nominee put forward by the leaders.

In her interview, Merkel said that member states and the European Parliament "have to work closely together and will do so".

The German chancellor is also in the awkward position of being in a governing coalition with the Social Democrats - political home to the centre-left candidate (Martin Schulz) for the commission post.

If the European Social Democrats were to win the elections, Merkel would need to endorse Schulz and lose the German commissioner post, traditionally taken by one of her centre-right party members.

Polls however suggest a close result with the centre-right slightly ahead but not gaining enough seats to have a majority, with a German-style grand coalition the most likely outcome.

No white smoke

EU leaders will meet on Tuesday to take stock of the result and kick off negotiations with the Parliament on finding a candidate that can muster a majority both in the Council - where member states are represented - and in the new legislature.

But any hopes to have a name emerge already next week would be misplaced, EU diplomats say.

"There will be no names discussed, don't expect any white smoke come out of the council," one source quipped, in reference to the Pope election process.

Instead, the council chief, Herman Van Rompuy, is expected to receive a mandate from the EU leaders to start negotiations with the European Parliament and member states on finding a candidate who can get a majority in both camps.

But another EU diplomat said there could be corridor talks among leaders, with the most obvious question being if Schulz or Juncker or an 'outside candidate' should get the job.

One line of reasoning is that if a female candidate is put forward - for instance Denmark's Socialist PM Helle Thorning-Schmidt or the current chief of the International Monetary Fund, the centre-right Christine Lagarde of France - the European Parliament would have a hard time vetoing them after having repeatedly asked for female candidates.

For his part, outgoing council chief Van Rompuy, a skilled Belgian negotiator, is seen as having his most difficult negotiation ahead.

"This will be his legacy, much more difficult than the EU budget negotiations" one EU diplomat says.