The findings come in a survey presented on Wednesday in Stockholm.
“I don’t believe we have ever had such strong pro-EU opinion,” said Professor Sören Holmberg, one of those behind the poll.
The findings were gathered in a postal survey sent to 6,000 Swedes by the SOM Institute last autumn. Of those who replied, 43 percent were positive towards EU membership, while 31 percent were negative.
The percentage of negatives has never been so low since Sweden joined the European project in 1995, nor has the gap between pros and antis ever been so large.
Other polls in the past year from Eurobarometer and Statistics Sweden point to a similar trend.
Possible reasons put forward by Holmberg and colleague Rutger Lindahl for the shift in opinion is that Swedes have noticed a number of improvements that they put down to membership. The EU takes some of the credit for Sweden’s improved economy; Swedes also put reduced food prices down to membership. The current focus on climate change is also thought to benefit the EU.
Those groups most positive towards EU membership are men, the middle-aged, the highly educated, immigrants, city-dwellers and southern Swedes.
Opposition to membership is highest among women, the young, those with low levels of education, members of the LO union confederation, rural dwellers and people living in the far north of Sweden.
Those who vote for the Eurosceptical Left and Green parties are increasingly pro-EU. Green supporters particularly are more in favour of membership than before. Holmberg said the party itself is split on the issue.
“The Green Party’s demand that we leave the EU increasingly has the same status as the Social Democrats’ demand that we become a republic,” he said.
Homberg said that the Sweden Democrats would in time come to be seen as the most anti-EU party.
The poll also asked voters what they thought about Turkish membership of the EU. Only 10 percent thought it was a good idea, a low figure given Sweden’s image as a supporter of Turkey as a candidate country. Other polls have previously produced positive results when people were asked whether Turkey “should be part of the EU in the future.”
Some 40 percent of those asked said they were in favour of EU cooperation on defence. 24 percent were against. Rutger Lindahl points out that this doesn’t mean that Swedes want a common European defence force. The support is mostly for EU cooperation in international peacekeeping missions.