All of the political commentary recently about the Tory Party's wooing of the two main unionist parties has dwelt on the possibility that the Tories might need the extra support in the British parliament in the event of a hung parliament.
But a hung parliament works two ways.
By definition it implies that no party has a majority of the seats, and any party that wishes to form the next government must seek additional support elsewhere. Hence the Tories increasing desperation to hoover up the unionist seats.
But the same can work for Gordon Brown too.
If the Tories do not have a majority then Labour will also have an opportunity to try to cobble together a coalition – either formal or informal – to return to power. Little is said of the smaller British parties; the Liberal Democrats, the SNP and Plaid Cymru, but all of them would have a preference for a Labour government over a Tory one. The Tories calculation is, no doubt, based upon an assumption of Labour being able to count on the support of all three – with the precise balance being dependent upon the small number of unionist seats.
At present the unionist seats are divided between the UUP (one) and the DUP (nine). The UUP's seat is held by the anti-Tory Sylvia Hermon, thereby adding to the Tories problems. Only if one of two things happen can they be assured of the extra support from Northern Ireland.
Firstly, the UUP (rebranded as UCUNF) has to win some extra seats. This is possible, even likely, but the number may be limited to one or two.
Secondly, the DUP has to lend the Tories its support. If the DUP retains most (or all) of its nine seats, then it is the DUP, and not the Tories allies in the UUP, who matter.
And the DUP will matter to Gordon Brown just as much as to David Cameron.
If Brown can 'win over' the DUP, and they retain most of their seats, this could be enough to deny the Tories their majority, and perhaps even deliver one to Labour.
So, in the current 'last-chance-saloon' negotiations going on in Belfast, there must be a temptation for Gordon Brown to give the DUP something – not to save Stormont, but to save Gordon. Antagonising the DUP may end his inglorious reign – and for nothing.
A British prime minister in a position of strength can be a neutral arbiter, but a British prime minister in a position of weakness, coming up to a tight election, cannot be neutral. Sinn Féin should be very conscious of this. Brown may be physically in the room, but mentally he is in May 7th, waking up to the post-election parliamentary arithmetic.