Update - Friday 9 June -23:45 BST
What a day. This time last night, the two main parties were pouring cold water all over the exit poll that put Theresa May's future in doubt. Tonight that question is very much on Tory minds.
She said today that she wants to stay and is in the process of working out how to deal more closely with the DUP (not without controversy) to get her business through Parliament.
Yet, there is an increasing mood that she might not get the chance to do so for very long. One minister predicted that, "slowly and reluctantly", the party might rally round her.
But sentiment in the party, never scientific, seems to be drifting away from allowing that situation to happen.
Three MPs have publicly questioned her right to stay on. One senior Conservative told me tonight she "has to go", suggesting she has a "responsibility to the party" to get the Queens Speech through, show the Conservatives can form the government, and then she ought to move aside.
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Other MPs are gently exploring the possibility of submitting letters to the chairman of the 1922 committee - 48 would be required to trigger a leadership contest.
Another former minister told me: "I just can't see how she stays."
To stay, there are already demands that Theresa May changes her ways of working. Her loyal chiefs of staff could be forced to go and a deputy prime minister might be appointed to create a less brittle and vulnerable government.
But moves from her might not be enough. Her gamble may not ultimately have just cost the Tories their majority, but for her, her political career.
This situation is changing fast and could feel totally different by the morning. But the rallying round the prime minister that has given her the chance to form a government may turn out to be only a brief window of opportunity - a space to allow her the time to come to her own conclusions.
Update - Friday 9 June 11:30 BST
She stays, for today. After a few hours of wild uncertainty, Theresa May will head to Buckingham Palace to seek permission from the Queen to form a government. She has the understanding and assurance from the DUP to be able to form a government, it seems.
The PM has experienced a political disaster of her own making. But uniquely perhaps for a prime minister in this situation she is, despite her ruthless party's DNA, planning to stay. The reason? Brexiteers don't want to rock the boat. No-one wants another election. And there is paranoia, whatever the EU says publicly, that Brussels would use the opportunity to cause the maximum amount of trouble. The way it's hoped at top levels of the party to avoid that is to leave 'the boss' as they call her, in place. But only for now.
I am yet to talk to a Tory source today who believes she can stay for as long as she likes. She is being seen as a caretaker PM, here for continuity at a time of great volatility - strangely the sort of reasons cited when she was nominated for the leadership. That was of course, before Theresa May revealed herself to be a gambler too. A trait only revealed once she moved into Number 10 - a trait that might be her political undoing, even if she keeps the address for now.
Update - Friday 9 June: 07:30 BST
In the last few minutes the PM has made it plain she will try to stay on and form a government. That's her right to do so, and as the party with the largest number of seats and votes the Tories will almost definitely form the next government.
But there is already pressure on her to go.
The question is not just whether enough Tory MPs are happy to keep backing her but also if it is vaguely realistic for her to stay on with her authority so challenged.
Update - Friday 9 June: 05:00 BST
The conversations have started not just about whether the Tories will be able to form a government, but whether or not Theresa May can stay in her job.
There is no one prevailing mood inside the Tory party. As I write, Mrs May is holed up with her advisers inside Tory HQ. But a former minister Anna Soubry has called for her to "consider her position" - political code for calling for her to resign.
Another senior MP tells me 'I can't see how she can stay'. A minister texts to say the Tory party is 'absolute monarchy, ruled by regicide and that's the territory we are in'. One Tory source says it is '50:50' that she will quit in the morning.
But others are urging caution, calling for reflection, a period of calm. It's clear the Tory party won't allow her to stay on to fight another General Election campaign in some years hence.
But cooler heads may press on her to stay, not to walk away. This is the election none of the main parties predicted.
Just as David Cameron finished off his own career by gambling with the EU referendum he didn't have to have, Theresa May has followed him by calling a national vote when it was not required, because of our relationship with the European Union, and ended her career in the same way.
Update - Friday 9 June: 02:15 BST
It's only just after two am. There are lots of seats to come in. But at this stage, Tory ministers are saying they do not expect to outperform the exit poll. That means, despite all of those Tory expectations, that confidence they regained in the last week or so of the campaign, the disbelief there was when our exit poll was announced, that privately at the highest level the Conservatives are now beginning to give up on achieving a majority.
It's just not clear yet whether or not they will be the largest party. Our exit poll suggests that they will. But either way, Theresa May is damaged, "strong and stable" sounds less like an irritating political catchphrase, and more like a parallel universe. She called this election only because she thought she would achieve a much bigger majority than the Tories already had.
Even if the Conservatives still end up ahead in terms of the number of seats, her authority looks set to be seriously damaged. It is hard to see how her reputation will recover, and she will have achieved the opposite effect of what she had hoped. This election could produce a more uncertain political picture, a wounded Prime Minister trying to take on the most complicated task any Prime Minister has faced - that's if, of course, the Tories remain the largest party, and she hangs on.
Thursday 8 June: 22:50 BST
If these numbers are correct, Theresa May played a high-risk political game and has lost it - she didn't have to call this election, and only did so in order to give herself a mandate and breathing space during the bumpy ride of Brexit.
Just a few weeks ago at the start of all of this she seemed unassailable, but a shaky campaign and an insurgent Labour Party may have dashed the Tories' hopes.
This exit poll result is not what either parties were predicting privately - this would be another political surprise - the public again defying the expectations of both the main sides.
The Conservatives do look set to be the largest party - it's not clear on these numbers if they will be able to govern alone.
Theresa May's promise throughout was to offer her catchphrase "strong and stable leadership" - instead she may end diminished - but only of course, your votes, and the real results, will determine through the course of the night what really happens next.