I was offered a bet the other day. But, being Northern Ireland, it had nothing to do with sport, and everything to do with politics.
All I have to do to turn £10 into a tidy bundle is predict, within a margin of 10 votes, the outcome of the Ulster Unionist Council vote tomorrow. Short of tracking down each of the 860 delegates, it's a difficult one to call. David Trimble is favourite to win. But by what margin? The Orange Order block vote is likely to swing against him, giving the No camp the comfort of the first 120 votes.
When Mr Trimble has gone to the council on other big issues, such as support for the Good Friday agreement, one in three have stood against him.
This week they have been bombarded with black propaganda, including letters of support purportedly from Sinn Fein, and videos of IRA victims who don't want the Mitchell deal to work. The Ulster Unionist Party is nothing if not democratic.
No leader of any party is more accountable to the rank-and-file membership. Thus the future of the Good Friday agreement, the peace process, and David Trimble's leadership hang in the balance.
Faced with such daunting opposition, other political leaders might find a way of implementing their plans without throwing themselves at the mercy of an unpredictable and anxious membership.
Tony Blair, of course, made an exception when he had to rid his party of the cumbersome Clause IV which committed the old Labour party to its unelectable socialist agendas. But would he place his leadership on the line today?
He would do everything in his power to avoid such a scenario. So too would Gerry Adams. When Mr Adams addressed the Sinn Fein faithful earlier this week, there was no question of putting the deal he negotiated on the party's behalf to the vote.
Political leaders sleep soundly in their beds only when secure in the knowledge they can always win. Mr Trimble, supremely calm and collected these days in the face of crisis, a skill he learned only in the later years of his captaincy of the UUP, does not have the appearance of a man who has been losing much sleep, but doubts still linger.
This is because it is difficult to gauge the impact of the whole carefully-managed (though increasingly desperate, and often obstreperous) black propaganda campaign mounted to end Mr Trimble's dreams. It is difficult to evaluate whether Gerry Adams helped or hindered the UUP leader's campaign by remarkably telling his republican brothers and sisters that Mr Trimble has played a central role in winning the IRA over to the peace accord.
For some unionists, that's like being praised by the Devil for convincing your friends Hell isn't such a bad place. It is difficult also to predict what influence has been exerted on the party membership by the Northern Secretary, Peter Mandelson. He has run the gauntlet of derision with a fair measure of alacrity while being introduced to the particularly vicious brand of personal insult in which Ulster country folk excel, as he did the rounds of the constituency associations with Mr Trimble.
The insults, it should be said, came from the rowdies who gathered outside the halls. Inside, the mood was generally businesslike, if a little fraught at times. It was a measure of the importance Mr Trimble places on the Mandelson contribution that at some meetings, the UUP leader's input was virtually invisible. Mr Mandelson was encouraged to occupy centre stage.
Nor have we heard much from deputy leader John Taylor, whose contribution to tomorrow's debate will swing the vote by more than a few per cent. In typically astute fashion, and with a keen eye for long-term political survival, Mr Taylor has remained on the margins of the debate.
In fact, during the last week of the Mitchell negotiations, he wasn't in the debate at all, preferring to talk politics with the Mullahs of Iran.
Yet come tomorrow, all eyes will be on him. Optimists in the Yes camp recall that hours before the signing of the Good Friday agreement, the honourable member for Strangford wouldn't touch it with a 20 ft barge pole.
Which way will he swing?
The respected BBC analyst Stephen Grimason told me this week the scene is set for Mr Taylor to rescue his leader. But Mr Taylor is close to people like David Burnside, unionism's London spin doctor, who has already signalled his opposition.
It could be that Mr Trimble and Mr Taylor are playing the old hard-man, soft-man routine, determined to wring from Peter Mandelson the cast-iron assurances which would protect the UUP in the event of no decommissioning. Another sage dismisses the idea. "Unionism isn't that clever," he remarked.
So will Mr Trimble grasp the glorious prize, or will he be finishing the resignation letter he is rumoured to carry in his pocket?
His campaign has not exactly been high profile, while the dissenters have everything in their favour. The prospect of sharing power with Sinn Fein still sends chills down the spine of every traditional unionist. It is all too easy for Mr Trimble's enemies to exploit these deeply held suspicions and long-standing grievances.
But if the UUP Council reflects the overall mood of the unionist people, Mr Trimble will triumph, and by a healthy majority. Everywhere I go I meet unionists who want the deal to be given its chance. Mr Trimble is assured of solid support from the business community. Civic unionism is weighing in behind him. He has engendered a greater level of middle-unionist support for his policies than any other party leader in recent history.
They are rooting for him on North Down's Gold Coast, on the leafy boulevards of Stranmillis and Malone, even in the more comfortable cul-de-sacs of Ian Paisley's mid-Antrim heartland.
Mr Trimble's misfortune is that so many of those who support him quietly from the sidelines are powerless to influence the decision, the price he pays for inheriting a legacy of dogmatic unionism which did not appeal to the middle classes.
In this mini-referendum, Mr Trimble would no doubt be happier if he could test the deal among the unionist people as a whole. A survey in yesterday's Daily Mirror, not noted for its leanings towards the unionist community, consistently showed more than 70 per cent of Protestants in favour of the deal in every constituency.
What he would give for that kind of outcome tomorrow! In a democracy a majority of one is still a majority. In reality, it is only when the 500th vote in favour of the deal is counted that David Trimble and his supporters will breathe a deep and collective sigh of relief.
Geoff Martin is editor of the Newsletter