Even if only 45 percent of Scots voted for independence last year, they could still divide the United Kingdom in May’s election.

Polls conducted by the Conservative peer Michael Ashcroft and released on Friday confirm that the Scottish National Party is set for a landslide victory next month.

Taking Lord Ashcroft’s latest polls into account, May2015, the New Statesman‘s election website, predicts that the nationalists will win 54 out of 59 Scottish seats in Westminster, an increase of 48. By far most of the seats it would take are now held by Labour, denying that party the chance to win an outright majority and likely forcing it into an awkward coalition with the SNP.

Labour has ruled out a formal coalition with the Scottish nationalists but both parties have left open the possibility of an informal alliance under which the SNP would support Labour policy on a case-by-case basis.

That is a much worse outcome for both Labour and Britain as a whole. As Dan Hodges, a former Labour Party and trade union official, argues in The Telegraph, “At that moment the government of the United Kingdom would effectively be held to ransom by a party that wants to see the United Kingdom broken up.”

A Conservative victory — which Hodges still thinks is more likely, despite Prime Minister David Cameron’s party polling neck and neck with Labour — wouldn’t bode well for Britain’s future either. Whereas Scotland would have dispatched, “virtually en masse,” left-wing secessionists to Westminster, they would be government by a right-wing pro-union party.

Anyone who thinks this scenario would form the basis for the continuance of a United Kingdom are deluding themselves. A more disunited political settlement is hard to imagine.

The Conservatives — like Labour and the Liberal Democrats — have promised to devolve more powers to Scotland in the wake of last year’s failed independence bid, including control over air passenger duties, housing credits, income taxes and winter fuel payments. The Scottish Parliament should also get additional welfare competencies.

For many Scots, it’s not enough. And under the first-past-the-post voting system, the minority in favor of independence could yet get its way. The other parties are splitting the pro-union vote. The SNP only needs to win pluralities in each constituency to win parliamentary seats. Given that it’s polling around 45 percent support — the same percentage that voted for secession in the referendum — that shouldn’t be too difficult to pull off.