BERLIN, Sept 15 (Reuters) - Support for Chancellor Angela Merkel's conservatives has slipped and over a third of Germans are still undecided how they will vote in the Sept. 24 election, an opinion poll showed on Friday.
The weekly survey, conducted by pollster Forschungsgruppe Wahlen for ZDF television, showed support for Merkel's conservative bloc falling 2 points to 36 percent - a result that would still make it the largest group in parliament.
Support for its nearest rivals, the left-leaning Social Democrats (SPD), rose by 1 point to 23 percent. The business-friendly Free Democrats (FDP) and the anti-immigration, euro-hostile Alternative for Germany (AfD) were both on 10 percent.
The far-left Die Linke stood at 9 percent and the left-leaning enviromental The Greens at 8 percent.
The poll of 1,383 voters, conducted from Sept. 12 to Sept. 14, also showed that 39 percent of those surveyed were still unsure how they would vote.
With the election likely to install six parties in parliament, up from four now, Germany will be marked by a more fractured political landscape after the vote. This could make coalition building difficult.
Friday's poll showed there would be sufficient support for both a repeat of the incumbent "grand coalition" of Merkel's conservatives and the SPD, and for a so-called "Jamaica" coalition of the conservatives, FDP and Greens.
However, Greens co-leader Cem Ozdemir sounded a sceptical note about a possible three-way Jamaica tie-up - a reference to the parties' colours: black, yellow and green.
"I don't see how we should get together with the FDP," he told the daily Berliner Zeitung.
The poll's margin of error was some 3 percentage points. With support for Merkel's conservatives and the FDP - natural allies who have ruled together in the past - at 46 percent, the margin of error suggests they could yet squeak into power.
A separate poll released on Thursday showed support for the SPD had slumped to its lowest level this year - at 20 percent - with Merkel's conservatives steady at 37 percent.
(Writing by Paul Carrel; Editing by Alison Williams)