Parliamentary speaker Andreas Norlén on Monday formally proposed Kristersson as the new prime minister of Sweden. The conservative leader said the other two parties in the centre-right Alliance – the Centre Party and the Liberals – had chosen not to be part of his proposed government.
Kristersson will be put to the test on Wednesday in what will in all likelihood be a historic vote: it has never happened before in modern times that a prime ministerial candidate has been voted down by parliament.
Under Sweden's system of 'negative parliamentarism', he does not need to receive a single vote in his favour. Instead, he must ensure that fewer than 175 members of parliament actively vote against him.
However, if he does not secure a last-minute deal with either the Liberal Party or the Centre Party, it currently looks unlikely that he will manage this.
If you assume that all 144 MPs representing the Social Democrats, Left Party, and Green Party will vote against him, then all it requires is for the Centre Party, with its 31 MPs, to join them, and his attempt will fail.
The leaders of both the Centre Party and the Liberal Party (which has 20 MPs) have previously said they will vote 'no', meaning Kristersson risks receiving more than 175 'no' votes.
The Liberal leader Jan Björklund on Friday reaffirmed in a letter to party members that he and his colleagues planned to vote 'no'. The Centre Party, however, has said that it will not make a formal announcement on its position until the speaker has formally tabled the proposal. So there remains a slim chance that the party's leader Annie Lööf, will change her position.
The Sweden Democrats have also so far not committed to opening the way for Kristersson, although they are widely expected to either abstain or vote in his favour.
If Kristersson's attempts fail, the speaker will begin a new round of talks, after which he is expected to propose a new prime minister candidate. That could be Social Democrat leader Stefan Löfven, but it could also be Annie Lööf, leader of the Centre Party, who could try to piece together a centrist government with the Green Party and some of her Alliance partners, relying on the Social Democrats for support.
The speaker can make four proposals for prime minister, after which, if none are accepted, a new general election will be called.