A progressive coalition could be on the horizon and every party except the Tories has reason to cheer – even Ukip

Even when the Tories and their newspaper backers threw the kitchen sink at Corbyn after the Manchester and London terrorist attacks, he skilfully turned the debate on to May’s decision to axe 20,000 police as Home Secretary. One message from this election is that voters have had enough of austerity

The Houghton and Sunderland South Labour candidate is re-elected, one of the first seats to be announced (Reuters)

When Theresa May called the election, it looked like a political masterstroke. Now it looks like an unnecessary gamble that has backfired spectacularly.

If the broadcasters’ exit poll is right, the Conservatives are struggling to get an overall majority and May’s survival as Prime Minister cannot be guaranteed. When her disastrous election campaign was derailed by her own unforced error on social care, senior Tories who were MPs in the last parliament discussed trying to depose her immediately after the election if she failed to win an overall majority. The possible successors named on the Tory grapevine were David Davis, Amber Rudd and Boris Johnson.

"She wouldn't survive as leader in a hung parliament after running the worst election campaign anyone can remember," one veteran Tory told me a week ago. The statement may be about to be tested.

The surprise exit poll figures even open up the possibility of a “progressive coalition” – which seemed a pipe dream when it was discussed during the election. Parliament could be split down the middle, with both the Tories and Labour short of the 326-seat winning post for a majority.

The Tories could probably rely on the votes of Northern Ireland’s Democratic Unionist Party, who had eight MPs in the last parliament and support Brexit. The DUP know how to drive a hard bargain.

The anti-Tory forces would almost certainly combine, trying to defeat a minority Tory government – on its Queen’s Speech, its Budget and, if the Tories remained in power, on crucial votes on Brexit. The progressive parties could try to shift May towards a soft Brexit, or at least a softer version of her hard Brexit. They could claim that voters had rejected the hard Brexit for which May sought a mandate. But that would provoke a backlash from hardline Tory Brexiteers.

The Brexit process, already complicated enough, could become even more difficult. The negotiations, due to start on 19 June, might have to be delayed, even though the clock is ticking towards is March 2019 deadline. It might even take another general election to resolve the impasse.

It would not be easy to bring Labour, the SNP, the Liberal Democrats, Plaid Cymru, the Social Democratic and Labour Party and the Greens together. But their common anti-Tory purpose will narrow the differences between them. The voters’ eyes will be on them; the parties would know another election could come soon, so they would want to act responsibly.

During the campaign, the Tories took every opportunity to warn that the only alternative to May’s strong government would be a “coalition of chaos.” It worked in 2015, when Ed Miliband’s hopes of becoming prime minister were sunk by the Tories’ warnings that he would be in the SNP's pocket. But it has not worked this time. The Tories, as the largest party, would try to hang on to power rather than hand over to what they would call “a coalition of the losers”. But it is not an accurate label.

The biggest winner of this election is Jeremy Corbyn. He has won a moral victory against all the odds. Very few Labour MPs in the last parliament gave him any chance of gaining seats; many were ready to say the party must have another leader if it ended up with fewer MPs. Now his position has been hugely strengthened.

At his ninetieth and final rally of the election on Wednesday, Corbyn declared: “Labour’s campaign has already changed the face of British politics. This is the new centre ground…. This is the new mainstream, and we have staked it out and made it our own.” It was seen as a coded way of saying he would stay on as Labour leader if the Tories won a majority. But the Corbynistas can claim vindication for their prediction that their man, having taken his party to the left, would now do the same in the country as a whole.

His manifesto was dismissed as an impossible wish list by the Tories. But it was popular and, with the Tories’ own goal on social care, switched the spotlight on to public services, Labour’s chosen territory. The pledge to abolish university tuition fees cut through to voters more than any other Labour policy and appears to have galvanised young people.

Even when the Tories and their newspaper backers threw the kitchen sink at Corbyn after the Manchester and London terrorist attacks, he skilfully turned the debate on to May’s decision to axe 20,000 police as Home Secretary. One message from this election is that voters have had enough of austerity.

The Liberal Democrats have had a miserable election, flatlining at 8 per cent in the opinion polls. But even with a small number of MPs, they could enjoy a lot of influence in the new parliament. During the campaign, Tim Farron ruled out a coalition with either May or Corbyn. His party is still scarred by the coalition government with the Tories from 2010-15. Farron, a possible kingmaker in a hung parliament, would surely find it impossible to do deals with the Tories because of their big differences on Brexit. He is more likely to look to cooperate with Labour on a vote-by-vote basis.

The SNP look certain to lose seats but will be big players in the new parliament. It is more likely to join forces with Labour, without a formal pact but with cooperation issue by issue.

If May had won the bigger majority she hoped for, Ukip would have been left with little purpose. But a hung parliament might just throw it a lifeline. May might be forced into some messy compromises on Brexit, allowing Ukip to accuse her of backsliding and claiming it still has a role as the “guard dog” of Brexit. There is something for everyone to cheer in the exit poll figures – except the Tories.