A right-wing faction has sided with the main centre-right party and deposed a centre-left government. Sound prophetic?

The scenario that could beset the UK next year has just happened in Sweden, less than three months after their most recent elections.

The Prime Minister, Stefan Lofven, leads Sweden’s biggest party, the Social Democrats, and governs in a minority coalition with Green Party, their fourth largest. They have failed to pass a budget after being held hostage by the Swedish Democrats, who demanded restrictions on immigration before allowing Lofven’s measures to pass.

The SDP-Green (or Red-Green) bloc hold 138 seats – 40 per cent of the chamber and well short of the 50 per cent they need. No party has won an outright majority since 1968, but coalitions have long proven effective: this is the first snap election since 1958.

The Swedish Democrats are the chamber’s third largest party, holding 14 per cent of its seats. As Lofven put in his press conference, they are effectively the kingmaker. They can currently choose between the Red-Green bloc and the centre-bloc of four parties – the Moderate, Center, Liberal People’s and Christian Democratic parties – who collectively hold 141 seats.

Lofven is gambling that voters don’t want the right-wing party to be in so powerful a position. He is trying to paint the centre-alliance bloc as having the same beliefs as the Swedish Democrats in the hopes of winning over the centrist parts of the centre-right.

As the Guardian Datablog recently detailed, Sweden admits far more asylum seekers per capita than any other country in the world. Immigration is a still only a pressing issue for a minority, but that minority is in control.

The new election will take place on 22 March, just over six weeks before the UK’s general election on 7 May.

The parallels with the UK are striking. As George Eaton detailed in September, Lofven came to power by increasing the SDP’s vote share by just 1 per cent – to 31 per cent – at a time when the Moderates’ share collapsed from 30 to 23 per cent. Disaffected voters turned to the Swedish Democrats, as some Labour voters increasingly seem to be doing now.

You can break down the extent to which Labour voters have been swayed by Ukip in the past five years using our new data portal: 'The Drilldown', which lets you separate polls into demographic groups, compare different pollsters and track recurring questions. For more on how and whether the UK could face two elections next year – which hasn't happened since 1974 – click through for our recent feature.

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