Senior Ulster Unionists now say Mr David Trimble's chances of re-election as First Minister of Northern Ireland next week could turn on a single vote.
Their stark assessment coincided with indications that the British government is preparing to commit itself to the goal of transferring substantial policing powers to the Stormont Assembly by 2003.
In a move which would underline London's belief in the long-term durability of Northern Ireland's devolved government, The Irish Times has learned that the commitment to transfer non-terrorist policing functions to Belfast may be spelt out in the forthcoming plan for the implementation of the North's Criminal Justice Review.
However, news of the plan, which might otherwise be seen as a significant boost for Mr Trimble, came as senior party colleagues conceded that just one vote could determine his bid to resume the office of First Minister in the power-sharing Executive.
With the all-important meeting of the Assembly expected next Friday, usually reliable unionist sources said their "best-case scenario" would see the North Down Assembly Member, Mr Peter Weir, abstain, so allowing Mr Trimble to win a majority among unionists voting of just one.
Should Mr Weir vote with the presently-declared anti-agreement bloc, Mr Trimble could be prevented from resuming ministerial office, despite expected strong support for his decision to re-enter government with Sinn FΘin at today's meeting of the UUP's policy-making Executive Committee in Belfast.
Immediately after the IRA's disarmament move earlier this week some UUP sources questioned the determination of anti-agreement Assembly members attached to some of the smaller unionist groupings to bring the Assembly down, and were actually predicting victory for Mr Trimble by a relatively comfortable margin.
And it seems clear that both sides will engage in an elaborate game of bluff and counter-bluff all the way up to next week's vote.
However, the possibility of fresh Assembly elections appeared to be moving back up the agenda last night as senior Ulster Unionists heavily discounted earlier speculation that members of the Women's Coalition or the Alliance Party might "redesignate" themselves as unionists for the purpose of ensuring Mr Trimble's re-election as First Minister.
At the same time it became clear that some of Mr Trimble's Assembly colleagues were against the creation of what one called "an artificial unionist majority" to keep him in office, and would prefer in such circumstances to seek a new mandate in a fresh Assembly election.
One fear haunting those tempted by the election option is that Sinn FΘin might overtake the SDLP and that Mr Gerry Adams might thus emerge as a new Deputy First Minister.
Against that, some UUP strategists believe the IRA's start of a process of putting weapons beyond use could enable Mr Trimble to "mop up some of the smaller parties" and secure his base at Stormont.
The Northern Ireland Secretary, Dr John Reid, would have to decide between fresh elections and suspension should the Assembly fail next week to fill the vacant posts of First and Deputy First Minister caused by Mr Trimble's resignation on July 1st.
Meanwhile a war of words raged between the UUP and the DUP over this week's report by the Independent International Decommissioning Commission.
The former Ulster Unionist MP, Mr William Ross, claimed that the reported IRA event "reeked of stage-managed duplicity" and called for a meeting of the Ulster Unionist Council to determine the party's response.