The posters say it all: these are not just two rival politicians, fighting for the majority in the Bundestag that would entitle them to form Germany's next government. They are almost opposite characters, formed by very different life experiences, whose paths have crossed in politics only because of the extraordinary twists of Germany's history over the past 50 years.
All they have in common is their relatively poor beginnings. Whereas Gerhard Schröder had a hard-scrabble childhood - he never knew his father, who was killed on the eastern front at the end of the Second World War - Angela Merkel was in a secure and mostly happy family, the elder daughter of a Protestant minister assigned to a parish in East Germany before the Berlin Wall was built. Mr Schröder, living in the booming west, was an aspiring politician from his earliest years; Ms Merkel, in the grey and confined east, was an academic physicist with a conventional East German education who entered politics only as the country was well on its way to reunification. While Mr Schröder was a natural performer and agitator from his youth, Ms Merkel acquired the very different political skills needed to negotiate a quiet professional life in the east. Where Mr Schröder is outgoing, charming and galvanised by a crowd, Ms Merkel - even at the end of this intense campaign - comes across as shy. The world of modern campaigning, with its razzmatazz, its fortissimo theme music, its chanting cheerleaders and its elaborately staged photo-ops still seems foreign to her. It is something she seems to tolerate as a necessary accoutrement to an election, but not something she finds easy or enjoys.
Ms Merkel's particular misfortune in this campaign, of course, is to have been up against one of the most consummate campaigners in the business. Mr Schröder's political instincts are sure; he finds opportunities where no other politician could. It is almost entirely thanks to him that the SPD is now in contention, when it began the campaign more than 12 points down.
At the start of this week, the Chancellor mercilessly played on Ms Merkel's seeming distaste for the ruthlessness of politics. At a multi-party television forum, he was flirtatious, condescending and ruthless at once. He ridiculed for the umpteenth time her financial expert, Paul Kirchhof, "the professor from Heidelberg" for his "flat tax" scheme (which is not Ms Merkel's policy). He pointedly questioned her credentials to protect "the German family", even though she had been an entirely competent minister for families in the government of Helmut Kohl. He did not actually say, as his wife had done, that this was because she had no children - but it was disgracefully clear what he was driving at.
As the SPD closed the CDU/CSU's lead, Ms Merkel was criticised for not calling time on Mr Schröder's effrontery. Why had she not questioned the right of the Chancellor's wife to cast aspersions on her family credentials? Why had she not slapped him down good and proper for equating Professor Kirchhof's academic projects with her party's tax policy? Why had she allowed Mr Schröder to place her on the defensive, as though it was she who had a defective record in government, when it was he who had presided over a post-war record of five million unemployed?
One answer would be that her initial double-digit lead blinded her to the danger that Mr Schröder presented. More plausibly, she may have hoped that she could win by force of argument. At her rallies, as at the one televised debate with Mr Schröder, she had all the facts at her fingertips and presented her case - whether for tax simplification or for keeping Turkey out of the European Union. She treats her audiences as intelligent grown-ups who can take their politics straight, without the baubles of entertainment.
Mr Schröder's approach is rather different. Ms Merkel's attempt at a populist fightback, with accusations - proved yesterday - that the Schröder government had a secret "poison" list of swingeing spending cuts to be implemented after the election, may have come too late to make a significant difference in how Germans vote. But it is a measure of voters' serious engagement in this election that Ms Merkel, even with her clear aversion to self-publicity, her often unsmiling aloofness and her reticence with crowds, still has the best chance of becoming the next chancellor.
And if she does, Germans will have to get used to a new leadership style in Berlin, as well as some sharp changes in policy. It is sometimes said of Mr Schröder that he is full of words and gestures, but the content is rarely as substantial. With Ms Merkel the reverse could be true.
She may have turned her back on the Marxism-Leninism that suffused her school and student years in favour of the free market and free choice, but she has retained the ordered and methodical approach to problems that she was taught then. She also preserves the determination that took her to a doctorate in physics from Leipzig University and thence to a research job at the East German academy of sciences. If she wants to get something done, she persists, looking for different approaches, but never losing sight of the objective.
This is one aspect of the flexibility many East Germans had to develop in dealing with their authorities. She is said to have a facility - doubtless developed in her academic years in male-dominated departments - of flattering vain men, which has served her well in German politics. Nor, despite her difficulties in countering Mr Schröder's flamboyance during this campaign, is she inexperienced in the rough and tumble of national politics. She has a streak of opportunism that helped her switch from academia to politics when East German Communism collapsed. As a protégée of Helmut Kohl, when he was the hero of reunification, she was the first to recognise that he was doomed when implicated in a scandal over party funding.
Her public dissociation from the Chancellor in an article for the Frankfurter Allgemeine newspaper propelled her to the leadership of the CDU over the heads of several other (male) aspirants. Despite the inevitable resentment and back-biting, they were unable to depose her.
As diffident as Ms Merkel often appears in public, in smaller gatherings where exchange and argument is expected, she is assured - which may explain her much better than expected performance in the televised election debate. Even in a small circle, though, the shutters immediately come down when she is asked about her private life. Some trace this to her upbringing in the east, where many people, especially professionals, learnt the value of discretion early. But she also comes across as a naturally private person, intent on keeping her home life as far as possible out of the public domain, even if, as it seems, there are no skeletons to hide.
In any case, East Germany was in some ways more permissive for women than the West. Divorced after a short and early marriage, she lived with Joachim Sauer for many years before marrying him in 1998 under pressure from the family-values CDU. A chemistry professor with an international reputation in his field, he has a similar dislike of public life. A lover of Wagner, he has kept such a low profiles that he is known on the campaign trail as the "phantom of the opera".
Only a little more is known about Ms Merkel's life outside politics. What has been gleaned by interviewers over the years is that she is a competent cook, enjoys mountain walking - not least because mountains make communications by mobile phone difficult - and shares her husband's Wagnerian enthusiasm. They go to Bayreuth every year.
As this election races towards a photo-finish, a candidate's every argument, every character trait and every unchallenged slur has the potential to influence the result. Polls out yesterday, the last before the election, show neither Ms Merkel's centre-right alliance nor Mr Schröder's Social Democrats with a certain majority, even in harness with a partner. Either one of them could nudge a coalition above the 50 per cent needed to form a government, or fall just tantalisingly short.
The three-week campaign has shown that Germany, like many advanced states, is almost evenly divided between political left and right, and between continuity and change. It has also shown that Germans, like many others, find it hard to decide whether they want a leader for the head or the heart. At least in Angela Merkel and Gerhard Schröder, Germany's voters have a very clear choice.Reuse content