The debate about who should fill the non-party post has been bedevilled by party politics, ahead of today's election in the Berlin Reichstag by the 662 members of the German parliament, plus the same number of delegates nominated by 16 regional parliaments.
This is the first time for 25 years that the election has taken place in Berlin, and is also the first presidential election since German unity in 1990.
Still seen as the most likely winner is Roman Herzog, senior judge and preferred candidate of Helmut Kohl's Christian Democrats (CDU). In order to win, however, he will also need the votes of the CDU's junior coalition partners, the Free Democrats (FDP).
Some leading Free Democrats have threatened to vote for the Social Democrat Johannes Rau who is by far the most popular candidate in the country at large. Most observers still only give Mr Rau an outside chance. But the FDP hesitation, and even suggestions of possible defections within the CDU camp in the secret vote, mean CDU leaders are nervous.
The voting system requires that, in the first two rounds, an absolute majority is required. With four candidates in the running, this is unlikely to be reached. In the first two rounds, Hildegard Hamm- Brucher (the FDP's official candidate), and Jens Reich (a leader of the East German pro-democracy movement in 1989, and standing as an independent candidate) will gain some votes. It is the third round, in which a qualified majority is sufficient, which therefore looks set to be a run-off, in effect, between Mr Herzog and Mr Rau.
The German president combines a quasi-monarchial role with providing moral leadership. The arguments over who should succeed the much praised Richard von Weizsacker have therefore often concentrated on what image of Germany the candidates would convey to the rest of the world.
If Mr Herzog is rejected by today's mini-electorate, the knock-on effect would be enormous. The implied defeat for Mr Kohl would seriously damage his attempt to portray himself and his party as 'the natural winner' for the October parliamentary elections.Reuse content