England closed the battle to get into the other. The UK goes to the polls this Thursday to elect a Parliament which, in the coming weeks, should provide a stable government for the world’s sixth-largest economy. A task that, if polls are not mistaken and there are no last-minute twists, seems complicated.

The intensive seven-week campaign has yet to sever the technical ties between the two parties that have provided the country’s prime minister uninterrupted for nearly a century. The Conservatives and Labor came to truth day with an estimated 34% of the vote each. Translating into seats, in an electoral system in which only one MP wins for each constituency, would give Prime Minister David Cameron’s Conservative Party a slight advantage. But both will be a long way from the 326 seats – 323, if you take into account that Sinn Fein used to not take it alone – which it takes to rule itself.

The catastrophe that polls predict for the centrist Liberal Democrat Party, which will lose half of its support after five years as a minority partner in a coalition government, will make it an insufficient ally to form a majority government. Only the Scottish Nationalist Party (SNP), which will storm Westminster with more than fifty seats and a mandate to oust David Cameron from Downing Street, can provide a stable government with members of the same Labor Party that looks set to be wiped off the political map north of the border. But Labor candidate Ed Miliband has ruled out that option. “There will be no Labor government if it means a deal or a coalition with the SNP,” he repeated last week in a televised questioning session with leaders.

Everything suggests that what will come out of the polls this Thursday will be what is known in Britain’s constitutional tradition as hanged parliament, or Parliament in disagreement. Conservative and Labor leaders rushed to campaign in the north of England on Wednesday, but their heads are already in negotiations that will officially open on Friday to try to build a stable government with a fragmented Parliament.

If Labor does better than the polls predict and wins more seats than tori, the scenario is relatively easy. David Cameron will ask the queen to call Ed Miliband and he will announce that he is ready to form a government. That would form a minority, with or without the help of the Liberal Democrats, who would run with the support of the SNP.

But if, as polls show, Tories they get more seats, without achieving the necessary to rule alone, the panorama is complicated. British constitutional law gives the prime minister the first attempt to form a government.

David Cameron could try. He will declare himself the winner of the election, announce his intention to form a government, and prepare for his Queen’s speech. This is the document Elizabeth II must read from her throne in the House of Lords at the official opening of Parliament scheduled for 27 May.

The Queen’s Speech outlines the Government’s legislative priorities and is debated and voted on in the House of Commons. In early June, the deputies will have to decide which document is a government project. If Cameron does not get the half plus one support of the deputies, there will be a condemnation motion that will force the prime minister to resign.

Labor and Scottish nationalists have announced that they will vote against the Conservative Queen’s speech. Likewise with Greens and Welsh Plaid Cymru. If they all got 323 votes, it would be Cameron’s end. A period of 14 days will then be opened for the new administration to try to gain the trust of the Chamber.

As several constitutional experts reminded this Wednesday, not one of the 107 pages of the Government Manual states that the party with the most seats must be the party that forms the Government. It will be shaped by “whoever is most capable of gaining the trust of the House of Commons.” But if, after a 14-day period, support for an alternative government has not been achieved, elections will be held.

Cameron will try starting Friday to redo a coalition agreement with the Liberal Democrats that would give him a government, if not a majority, at least something more solid. Nick Clegg has stated that he will speak first with the party that won the most seats and has warned that he will not enter any government that agrees with Scottish nationalists or UKIP. Conversations with government partners will still focus, most likely, on the red lines drawn by Tories what the liberal-democrats lack: the celebration, yes or yes, of a referendum on immortality in the European Union.

David Cameron will use his condition as Prime Minister to convey an image of responsibility and continuity in parallel with negotiations. Meanwhile, if the polls give him the chance to form an alternative government, Ed Miliband will remain in custody. He would try to ensure that his deputy and those of his potential allies would knock down his opponent’s queen’s speech, and would prepare for his assault on 10 Downing Street.