Elections in the North are never dull, but next month's Westminster poll promises to be one of the most exciting and important since the start of the Troubles. The future of the North's First Minister, Mr David Trimble, and the Belfast Agreement hangs in the balance.
The DUP has everything to gain and little to lose. In constituencies it isn't contesting - South Belfast and West Tyrone - it is urging supporters to vote for the sitting anti-agreement UUP MPs, the Rev Martin Smyth and Mr Willie Thompson, both outspoken critics of Mr Trimble.
The aim is to damage Mr Trimble's leadership, and the agreement, as much as possible. In last September's South Antrim by-election, the DUP massively increased its vote to take one of the UUP's safest seats.
It hopes to retain that constituency and snatch at least two more from its rival in North Belfast and Strangford.
The UUP is also in danger of losing another two seats, West Tyrone, and Fermanagh and South Tyrone, to nationalists.
The party is facing a strong DUP challenge in East Londonderry, East Antrim and Upper Bann, although it should retain these seats. The UUP holds nine Westminster seats, but the only truly safe one is Lagan Valley, where the sitting MP, Mr Jeffrey Donaldson, would be Mr Trimble's rival in a future leadership contest.
The DUP believes that if Mr Trimble loses two or more Westminster seats and 25 or more council seats - the local government elections will also be on June 7th - he will face a leadership challenge at the Ulster Unionist Council meeting later that month.
Officially, the UUP is confident. It describes South Antrim as a blip and says voters don't repeat by-election behaviour at a general election. Leadership sources acknowledge the battle to retain North Belfast and Strangford but believe they could pick up North Down.
The UUP will select its candidate tonight, but the front-runner is Lady Sylvia Hermon, wife of the former RUC chief constable, Sir Jack Hermon. North Down is a middle-class, conservative and generally pro-agreement constituency, and officials believe Lady Sylvia would be an ideal choice.
Anti-agreement unionists insist the UK Unionist Party leader, Mr Bob McCartney, will win. They say the UUP's de-selection of its previous anti-agreement nominee, Mr Peter Weir, has a strong whiff of manipulation which the electorate will rebel against.
The UUP desperately needs to win this seat if it loses elsewhere. It must also hold Fermanagh and South Tyrone, currently held by Mr Ken Maginnis, who is not contesting the election. A Trimble supporter, Mr James Cooper, will be its candidate.
However, as an anti-agreement unionist and survivor of the 1987 Enniskillen bomb, Mr Jim Dixon, will be splitting the unionist vote, the seat could go to Sinn Fein.
Without Mr Cooper or Lady Sylvia, Mr Trimble would be the only pro-agreement UUP MP at Westminster.
In North Belfast the DUP's Mr Nigel Dodds is likely to unseat the pro-agreement UUP MP, Mr Cecil Walker. And the DUP's Ms Iris Robinson is favourite to win Strangford from the UUP.
The UUP's election campaign could be rather contradictory. On the one hand, it will sell the agreement and point to its successes: getting rid of the Anglo-Irish Agreement and Articles 2 and 3, cementing the principle of consent, securing the return of devolution, and the inspection of Provisional IRA arms dumps.
Yet Mr Trimble's statement yesterday that he will leave the Executive by July if there is no decommissioning, shows he realises he must retain credibility with voters who believe he has already compromised too much.
Until the SDLP's decision to put up the Agriculture Minister, Mrs Brid Rodgers, in West Tyrone, most observers believed this would be Sinn Fein's election.
The party was confident its vice-president, Mr Pat Doherty, would take West Tyrone, but the local SDLP representative stood aside for the high-profile Mrs Rodgers, who is now the favourite.
Sinn Fein, however, could still pick up Fermanagh and South Tyrone. It believes it will generally benefit from nationalist anger at Mr Trimble's "breaches" of the agreement.
The SDLP reckons it will go close in south Belfast, a growing Catholic constituency, and out-poll Sinn Fein in north Belfast.
It says it has defended the agreement against Sinn Fein and UUP game-playing over the past three years. It also argues that it has dramatically improved its internal machinery and media profile.
Of the smaller parties, observers predict a further decline in Alliance's vote. The Progressive Unionist Party and the Ulster Democratic Party are likely to suffer severely from the loyalist feud. The Women's Coalition is not tipped to win any seats.