Grand coalition looms as Germany's election hangs in balance Angela Merkel's hopes of winning a third term as German chancellor at the head of her current conservative-liberal coalition are hanging in the balance, with the latest opinion polls suggesting she may be forced to negotiate a "grand coalition" with the centre-left Social Democrats. Politbarometer, the leading poll published on Friday by ZDF, the second German public television channel, puts the combined vote of Ms Merkel's Christian Democrats, and her liberal Free Democrat partners, at 46 per cent, just one percentage point in front of the combined opposition vote. But DeutschlandTrend, the weekly poll on ARD television, has just the reverse, with the combined opposition parties on 46 per cent, one point ahead of the current coalition. Both predictions are well within the normal margin of error for the opinion polls. "It is very difficult to read, because the polls are all over the place," said Andreas Busch, politics professor at Göttingen university. But a grand coalition has become more likely. If the ARD prediction were the outcome on September 22, when Germany's 61.8m voters go to the polls, it means that the far-left Linke party would effectively hold the balance of power. But because the Social Democratic party has flatly ruled out any alliance with the Linke, the most probable outcome would be a grand coalition. The only other possible two-party alternative would be a hitherto untested alliance between the Christian Democratic Union and the Greens, which seems unlikely to gain majority support in either party. Pollsters and politicians expect the final week of campaigning to see significant further shifts in support, as all the parties seek to mobilise their own constituencies, and woo a high proportion of undecided electors. Renate Künast, joint parliamentary leader of the environmentalist Greens and their top candidate in Berlin, said that "most people decide in the last three days." "We have fewer voters really fixed on one party," she told the FT. More and more change allegiance in every election campaign. But her party, once seen a potential kingmaker, has slipped in recent weeks from a steady 15 per cent in the polls to just 10 per cent in the latest ARD poll, and 9 per cent in the Forsa poll for RTL television and Stern magazine on Wednesday. The loss of momentum for the Greens comes as the SPD had appeared to revive its fortunes, up two points in the Forsa poll to 25 per cent. But taken together, the combined "red-green" score of between 34 and 38 per cent is still well short of Ms Merkel's 45 or 46 per cent. Inside her CDU headquarters, however, there are growing concerns that the party may not poll as well as expected. Private polling suggests that support for Ms Merkel's coalition could be weakening, and the Free Democrats remains stuck on 5 per cent. CDU strategists fear that some regular CDU voters will vote tactically, giving their second votes to the FDP, to ensure they get more than the 5 per cent minimum needed to get into the Bundestag. That could become a real problem for Ms Merkel if the FDP poll under 5 per cent in the Bavarian state election on Sunday - seen as a pointer to the national poll one week later. In the last state election in Lower Saxony, a big switch of CDU voters to the FDP actually lost the election to a red-green coalition by fewer than 330 votes. Another worry for the chancellor is that the newly-founded eurosceptic party, Alternative für Deutschland, will poll better than the 2 to 4 per cent suggested in opinion polls. Pollsters admit that people who are tempted to vote for marginal parties on the far right and far left often refuse to reveal their choice over the telephone. Bernd Lucke, the AfD leader, is confident that his party will get more than 5 per cent, and therefore 10 seats or more in the Bundestag, which would be just enough to force Ms Merkel into a grand coalition as the only option with a clear majority.