In the September elections, the Social Democrats, the Greens and the Left party got four percentage points more votes than the four-party centre-right Alliance. In this poll, which in fact in an index that weighs together thre results of five different polls, carried out in November, the gap has narrowed to only 1,4 percent.
But political scientist Mikael Gilljam at Gothenburg University says the big surprise is that the parties in the minority government, the Social Democrats and the Greens, have not done worse in the opinion polls.
"Overall I am surprised. With all the visibility in the media, and that this is a competely new government, completely new prime minister and a new coalition that never has governed before - I am surprised they have not been harder hit," he told Swedish Radio News.
After the elections in 2010, the centre-right Alliance parties had lost much more in the opinion polls, he said.
With the uncertainties ahead of Wednesday's vote on the framework for next year's budget, there has been talk of the possibility that Prime Minister Stefan Löfven will be forced to call a new election. The two parties in government hold just under 38 percent of the seats in parliament. With the support of the Left Party, the government's budget will get more votes than the Alliances can scrape together amongst themselves.
The question is how the Sweden Democrats will vote, something they have said they will reveal on Tuesday. The custom in parliament is that you only vote for your own budget, and if that does not get voted through, you will abstain from further voting. But the Sweden Democrats have said they are considering voting for the budget put forward by the opposition, the Alliance. If they do so, it will be very difficult for the centre-left government to go on. Either the speaker of the parliament will have to start a new negotiating round, to try to bring forward a stronger government. And if that fails, Prime Minister Stefan Löfven will have to set a date for a new election.
Only once before has Sweden had a new election called, before the end of term, and that was in 1958. But it is not that unusual to have what is here known as a "government crisis". This is when a new government, for example to include other coalition partners, has to be formed during the course of one parliament, in order to be able to govern the country.