On the face of it, Julia Gillard appears set to become the new Prime Minister of Australia.
Kevin Rudd has chosen to fight for his job and, if defeated, he will be able to say he did just that.
But the early numbers would suggest he is likely to be robbed of the chance to ask the Australian people for a second victory.
Ms Gillard still looks like the reluctant challenger. She was persuaded to this course by the unions of the Labor Right, primarily the Australian Workers' Union, and by senior figures in the New South Wales Right.
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She now has the open support of the AWU and its secretary, Paul Howes, (who's not in Parliament but whose endorsement is indicative of a section of the party).
Former union heavyweight, now parliamentary secretary Bill Shorten, was instrumental in this coup. Likewise fellow Victorian union man, Senator David Feeney, South Australian Senator Don Farrell, Agriculture Minister and ex shoppies unionist Tony Burke, and the man the Prime Minister promoted into the ministry a year ago, NSW Senator Mark Arbib.
The union-dominated Queensland Right is now also behind Julia Gillard - a lawyer from the party's Victorian Left. Some sections of the NSW Left are saying they are with her too.
Still, it is an uncomfortable night for many - if not all - in the Labor caucus. These are terrible nights for a political party, when even the mutineers know they risk blowing themselves up. They will always put the need to hang onto power ahead of the feelings of their leaders. They will describe it as the "national interest" and many will genuinely believe that's what it is.
But it's about keeping the other mob out.
They know voters may decide that they would prefer that they get to choose their Prime Minister and not have factional leaders dictate to them.
That's what Kevin Rudd is hoping.
He is asking his colleagues to respect the fact that he was elected by the people, not factional heavyweights.
But the forces behind Julia Gillard hope voters will sigh with relief and find the choice between her and Opposition Leader Tony Abbott an easier one to make.
If Ms Gillard wins, she will become Australia's first female Prime Minister. It's the kind of history-making extra detail which will be used to persuade all those waverers on the backbench to make the boldest and bloodiest of moves.
If she loses - well, history tells you these things are rarely over after one challenge. One way or another, it's looking like it could be over for Kevin Rudd.
Politics is most certainly a swift and brutal business. Don't let anybody tell you it's not.
