Thirteen of the 18 seats are regarded as being as safe as houses and pretty much bereft of drama. Two of the others, one of which is held by Ian Paisley's deputy, Peter Robinson, will probably not change hands, but the remaining three are being intensely contested.
The fact that Sinn Fein is in contention in all three of those seats, together with IRA incidents such as the disruption of the Grand National, means that the results there will be the main focus of media and political attention, as the campaigns in them have been.
In terrorist terms, there may well be more IRA attempts to repeat that disruption. Politically, Sinn Fein's president, Gerry Adams, lost his party's sole Westminster seat in 1992: winning it back, perhaps with another one or two more, would help to ensure the republicans stay centre-stage.
In the event of a hung Commons, however, the focus would switch to David Trimble's Ulster Unionists. The party can be sure of eight seats, will probably take nine and might possibly have 10. Should the Conservatives find themselves in need of parliamentary allies post-election, the UUP may well find itself being wooed.
In the meantime, fierce scraps are going on within unionism as Mr Trimble and Mr Paisley dispute the share-out of seats, most notably the new constituency of West Tyrone. The particular quarrel there illustrates the type of demographic minutiae on which Northern Ireland elections so often turn.
Last year, in a different kind of election, John Hume's SDLP and Sinn Fein each secured 28 per cent of the vote. Mr Trimble's party had 18 per cent, Mr Paisley's 16 per cent. Despite the Hume-Adams relationship in the peace process, the parties are keen electoral rivals: both have a candidate and neither will withdraw in favour of the other.
With both the SDLP and Sinn Fein in the fray, an agreed Unionist candidate might just take advantage of the split nationalist vote and win. On last year's figures, the obvious thing for Unionists to do is to sink their differences and for either Mr Trimble or Mr Paisley to allow the other a clear run.
Yet although the approaches of the two Unionist parties overlap, in many respects the enmity between them is considerable, and both dearly want the seat. One of the features of Northern Ireland is that its 18 Westminster seats and three European seats are the only properly salaried elected political posts available, and competition for them is fierce.
If neither Unionist party gives way then the seat will almost certainly go to a nationalist; but it is impossible to say with any confidence which nationalist that would be. Northern Ireland voters tend to play their cards close to their chest.
Similar demographic sums are being totted up in neighbouring Mid-Ulster, where Sinn Fein last year took 29.7 per cent of the vote compared to the SDLP's 28.5 per cent. There will be only one Unionist candidate in that seat, which last year registered a 35 per cent Unionist vote: the question is whether nationalist voters perceive that either the SDLP or Sinn Fein can beat the Unionist, and swing in that direction in sufficient numbers.
The other possible Sinn Fein gain is in west Belfast, a traditionally bitterly hard-fought cockpit seat. To oust the SDLP incumbent Gerry Adams would first have to get out the Sinn Fein vote, and then have to hope that the small Unionist pocket of the constituency does not turn out to give the SDLP tactical votes aimed at keeping Sinn Fein out.
Overall, Sinn Fein could lose votes yet gain seats. Winning seats would be hailed in many quarters as a republican resurgence, yet the fact is that in many constituencies the outcome will depend on localised factors. Someone once said that all politics is local; in Northern Ireland that is especially true.Reuse content