STOCKHOLM (Reuters) - The lead of Sweden’s centre-left bloc’s over the centre-right Alliance has narrowed ahead of Sunday’s general elections, an opinion poll showed on Wednesday, with neither coalition set to win a majority of seats.

The Social Democrats, with its junior government partner the Greens and parliament ally the Left Party, are less than one percentage point ahead at 40.6 percent, the poll published by Svenska Dagbladet (SvD) showed.

The four-party centre-right Alliance was almost neck-and-neck with 39.8 percent, the SvD/SIFO poll based on 2,893 interviews carried out during Aug. 30 through Sept. 4 showed.

Neither bloc looks to have a real chance of securing a majority, with the anti-immigration Sweden Democrats, shunned by all other parties since entering parliament in 2010, polling at 17.1 percent.

Both Prime Minister Stefan Lofven’s centre-left bloc and the opposition Alliance, for which Moderates leader Ulf Kristersson is the candidate for the premiership, have ruled out striking a deal with the Sweden Democrats after the election.

Still, forming a viable government without their support will need parties in the two blocs, which have defined Swedish politics for decades, to break ranks and offer at least tacit support for their rivals across the aisle.

Graphic: tmsnrt.rs/2LmSZFD