That means the whole election apparatus has to get cranked into gear again for the third time in just ten months.
An election isn't just something you throw together, most parties plan their campaigns year in advance, but for the extra elections they will have much less time. And that goes for all the administration organising the election as well. This is the first time Sweden has had an extra election since 1958, but Hans-Ivar Swärd from the Swedish Election Authority says they are ready for the nationwide poll.
"The election authority must always be ready for new elections", he tells Radio Sweden, "you always keep in stock ballot papers, envelopes, things like that". He adds however that by law the authority is not yet allowed to do anything until the election is officially called on December 29th: "We can't do anything until we get the official decision from the government. We can of course plan in our heads, but we're not allowed to publish anything on our website or things like that".
Then after the 29th December the various political parties have to send the details of their new ballot papers to the authority, drawing up new candidate lists, and then voters will also have less time to cast their vote. Early voting will only last ten days this time round, and voters abroad will only have 20 days to have their say.
And the election authority are not the only people that will now have to get back up to speed, apart from the media, all the politicians and their volunteers will also have to out their campaigning boots on again and go out and start knocking on doors, this time in the middle of winter. Some of the keenest campaigners are the youth wings of the political parties. Rozgar Watmani is the national secretary of the SSU, the youth wing of the Social Democrats, and he says they are ready to go.
"Our members have already been campaigning, actually," he told Radio Sweden, "some members out in the country started campaigning and posting stuff on social media straight after Stefan Löfven's press conference."
He says they have to be prepared to meet people and spend long days campaigning, but adds: "It's not just about campaigning, it's also about which policy and which direction we go. Our members are ready and they enjoy campaigns, but they campaign for something greater, and this gives them the strength and power to do that."