FOLLOWED by a bevy of cameramen as if they were his retinue, Horst Seehofer, the premier of Bavaria, strode the halls of the palatial state parliament in Munich on the evening of September 15th. As he entered the hall belonging to his party, the conservative Christian Social Union (CSU), the packed crowd broke into rowdy cheers for “King Horst”. The CSU had just won an absolute majority of seats in the state parliament, letting it reign once again without a coalition partner, as it had done from 1966 to 2008. Even before the applause died down, however, one former CSU leader turned aside and privately said he worried about a different party.

For the biggest news in that Bavarian election, regarded as a curtain-raiser for Germany’s federal poll on September 22nd, was the electoral disaster of the Free Democrats (FDP). This small liberal party has been the CSU’s coalition partner in Munich since 2008, just as in the federal parliament it is the partner of the CSU and its larger sister party, the Christian Democratic Union (CDU) led by Angela Merkel, the chancellor. In Bavaria the FDP got only 3.3% of the vote, well below the 5% threshold needed to enter parliament. Now the FDP worries about being ejected from the federal parliament as well.

This possibility has upended the strategies of both the FDP and the CDU. Germans cast two votes on their ballots, the first for an individual to represent their district and the second for a party. It is this second vote that determines the percentages of the parties in parliament. The FDP’s leaders thus appealed openly to CDU and CSU voters to “donate” or “lend” their second votes to the FDP to assure its survival. “Anyone who wants Merkel as chancellor should vote FDP,” said Rainer Brüderle, its top candidate. His staff were busy plastering bright yellow or red stickers onto the party’s campaign posters across Germany: “second vote FDP”.

The CDU and CSU used to tolerate tactical voting by their own supporters to help the centre-right camp as a whole. Not so this time. Campaigning in Lower Saxony, Mrs Merkel said that “we have no votes to donate”. Fresh in her mind is a state election in Lower Saxony last January, when such tactical voting by CDU supporters for the FDP backfired, causing a zero-sum shift and handing the state government to the Social Democrats (SPD) and Greens. Moreover, a change in Germany’s electoral law this year means that, in effect, the second votes are the only ones that matter.

An internecine struggle has also broken out on the centre-left. For much of the summer, the larger SPD was flailing with its hapless candidate, Peer Steinbrück, nicknamed Pannen-Peer (gaffe-Peer), while the Greens appeared confident. But in Bavaria it was the SPD that increased its share of the votes since the last election there (admittedly, only from 18.6% to 20.6%), while the Greens’ share went down (to 8.6% from 9.4%). The two centre-left parties now have no realistic chance of forming a federal majority together.

The Greens have declined in recent weeks. They annoyed undecided voters with their calls for ever more nanny-state regulations, such as meat-free Thursdays in public canteens. A new-found focus on redistribution using tax rises also turned off much of their own base, which, in contrast to the blue-collar Social Democrats, is ecologically sensitive but also more educated and middle-class. And now they have a new problem. A pair of investigators has been researching the influence of paedophiles on the party in the 1980s. On September 16th they disclosed that Jürgen Trittin, one of the top Greens, personally signed off on a proposal by a municipal branch of the party in 1981 to decriminalise non-violent sex with children.

The centre-right parties together now poll at 44%, according to Manfred Güllner of Forsa, a pollster. The left parties in opposition also poll at 44%. This means that neither camp may get a majority of seats on September 22nd. The left parties could not form a coalition anyway, because both the SPD and the Greens have ruled out co-operation with Die Linke, a party that descends from the communists of East Germany and is considered too radical.

So the leaders of the CDU and SPD are discreetly preparing for a “grand coalition”, which may be the only way to form a government. Mrs Merkel is said to welcome this outcome, because she governed well with the SPD during her first term in 2005-09. It would be harder for the Social Democrats, who feel they were punished by voters in 2009 for being Mrs Merkel’s lapdogs. Mr Steinbrück, finance minister last time around, says he would not serve in a cabinet under Mrs Merkel again. Other leading Social Democrats are salivating over ministerial appointments.

Werner Weidenfeld, a professor at Munich’s Ludwig-Maximilian University, thinks that the FDP may yet get into the federal parliament, in part because its Bavarian fiasco mobilised its latent base. If so, the centre-right coalition still has a chance. Otherwise, a grand coalition is the likeliest outcome. But if the three leftist parties together get a majority, says Mr Weidenfeld, the SPD might be tempted to wait to mid-term and then abandon its grand coalition with the CDU in order to form a new government with its ideological cousins on the far left. Having railed against Die Linke in this campaign, the Social Democrats cannot team up with them right now. But in a few years, they may calculate that voters will overlook what they said today.