Germany's election campaign becomes tale of colour coalitions Whatever happens in the German election campaign over the next five-and-a-half weeks, the outcome will almost certainly be for another coalition government. Although Angela Merkel is the most popular politician in Germany, and her Christian Democratic Union is the front-running political party, it would be an extraordinary upset for the CDU - with its Bavarian sister party, the Christian Social Union - to win an outright majority. It is currently earning steady 40 per cent support in opinion polls, some 6-7 per cent short of the threshold required to gain outright control of the Bundestag. At this point in the election campaign, however, the game politicians play is to deny they have any intention of taking part in any coalition other than their first preference. So Ms Merkel is adamant that she wants to keep her present centre-right coalition with the liberal Free Democrats, although its record over the past four years has been very patchy. Constant bickering, especially between the FDP and the conservative CSU, has made the "black-yellow" coalition (named after the respective party colours) much less popular than its constituent parts. On the left, the Social Democratic party (SPD) and the environmentalist Greens insist that a "red-green" coalition remains their absolute ambition, even though they are currently polling a combined 40 per cent, well short of the majority threshold. The man who has now put the cat among the pigeons is Gregor Gysi, the sharp-witted and silver-tongued former Communist lawyer who leads the radical Linke - the Left party - in the election campaign. He declared last week that he would happily take part in a "red-red-green" alliance to replace Ms Merkel. His proposal has been scornfully dismissed by both potential partners. Indeed, the prospect of a "red-red-green" government is precisely the socialist scenario being presented by Ms Merkel and her allies as the horror alternative to their safe and boring conservative partnership. Peer Steinbrück, the SPD candidate for chancellor, is tired of denying that he will ever countenance such a connection. His argument is that Germany must be a stable international partner - for solving the eurozone crisis, and in the Nato alliance. But the Left party is anti-Nato and anti-EU. The Greens say much the same. But if neither black-yellow nor red-green coalitions has a clear majority, what is the alternative? A "grand coalition" of CDU and SPD is the one most Germans (52 per cent in a recent poll) would favour - and most of the outside world. Mr Steinbrück admits it is what Washington, London and most of the rest of the EU would like to see. But he is flatly against it. From the start of the campaign, he has said he would not serve under Ms Merkel in such a "black-red" alliance, although he was finance minister in the grand coalition she headed from 2005-09. He also fears it would split the SPD. Sigmar Gabriel, the SPD chairman, has said the party should have a national convention to decide on September 23, immediately after polling day. Other senior figures favour a party referendum. The chances are that grassroots members would opt to stay in opposition, bitterly remembering that they slumped to their worst postwar result - just 23 per cent - in the 2009 election. Another option would be "black-green" - an alliance between Ms Merkel's Christian Democrats and the Greens. There is a vocal minority in both parties that would like to try it, although Ms Merkel has described "black-green" as a "crazy idea." There is a deep cultural divide between the parties. The Greens have their roots in the student protest movement of the 1960s, which was a revolt against their parents" party - the CDU. The bitterness remains on both sides. Senior Greens fear they would lose up to 30 per cent of their party members. The only potential coalition that might see Mr Steinbrück as chancellor would be a so-called "traffic light" coalition of SPD, Greens and FDP (red, green and yellow). If a grand coalition is out, and so is black-green and red-red-green, it might be the one workable option. Rainer Brüderle, head of the FDP election list, says it is out of the question. SPD and Greens want higher taxes, he says, while the liberals are fiercely opposed. All of the current denials should be taken with a pinch of salt, however. When the post-election haggling begins, all the options will become possible.