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STOCKHOLM, Jan 25 (Reuters) - Support for Sweden's ruling centre-left Social Democrats party hit its lowest level for nearly 50 years, a major opinion poll said, mainly due to a sense the government was being overwhelmed by the biggest influx of refugees in the country's history.
The weekend poll by Sifo for daily Svenska Dagbladet showed the Social Democrats were supported by 23 percent of voters, their worst result since Sifo started surveys in 1967. The party got 31 percent in the 2014 general election.
In the space of a couple of months last year, Prime Minister Stefan Lofven went from saying "my Europe doesn't build walls" to saying "we have taken in too many for too long".
Sweden has now put in place border controls with its neighbour Denmark to stem the flow of asylum seekers that reached a record 160,000 last year.
"People are losing faith in the government's competence because they cannot control the (asylum) situation," said Peter Esaiasson, political scientist at Stockholm University.
Accusations that Foreign Minister Margot Wallstrom jumped the queue for an apartment in Stockholm owned by a union of blue-collar local government employees have not helped.
The Green Party, the Social Democrats' minority coalition partners, saw its support fall to 6 percent from 7 percent in the general election , putting the government well behind the four party centre-right opposition Alliance bloc.
The anti-immigration Sweden Democrats got 18 percent, above the 13 percent they won in the general election and remaining Sweden's third largest party.
The opposition centre right Moderates were up 3.5 percent in the poll at 26 percent.
A new election is not due until 2018, but falling support for the government could see Sweden's complex political map redrawn much sooner.
The government has so-far been able to function thanks to support from the Left Party and the centre-right opposition's unwillingness to bring down the coalition.
Neither bloc can form a majority without support from the Sweden Democrats, a tactic which all mainstream parties have ruled out.
Leading in the polls, the four party opposition Alliance may be tempted to try and take power, banking on the fact the Sweden Democrats have in the past tended to side most with the centre-right in parliament.
"If the Alliance increases its support in a number of further opinion polls, ... it may be the case that they will be less worried about forcing a new election," said Jonas Hinnfors, a political scientist at Gothenburg University. (Reporting by Simon Johnson and Johan Sennero; Editing by Alistair Scrutton)
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