Tony Blair has finally confirmed May 5th as the date on which he will ask the British people for a third and final term in 10 Downing Street.
The prime minister confirmed Westminster's worst-kept secret yesterday after making the traditional journey to Buckingham Palace to formally ask Queen Elizabeth to dissolve parliament next Monday.
On his return he told reporters of his and Labour's "driving mission" for a historic third consecutive term in which to entrench "hard- won economic stability", accelerate change and further widen the opportunities available to the British people.
However, Mr Blair has already ensured the unique nature of the forthcoming contest by becoming the first prime minister to seek a renewal of his mandate while having publicly committed himself to standing down before the end of the next parliament.
The prospect of a change of Labour leadership, or even, though heavily discounted, a Conservative government, carries potentially significant implications for the future of British policy towards Europe and Northern Ireland.
The outcome of the Westminster general election in Northern Ireland could determine whether David Trimble and Mark Durkan respectively can remain as leaders of the Ulster Unionist Party and the SDLP. It should also decide whether the UUP and SDLP can remain as political forces or whether after polling day they will be swamped by the onward march of the DUP and Sinn Féin.
In Northern Ireland, scores of candidates will compete for 18 Westminster seats, while several hundred more will fight for almost 600 council seats in the local government elections also on May 5th.
The most crucial election battles are in Upper Bann where Mr Trimble is under pressure to hold his seat from DUP candidate David Simpson and in Foyle where Sinn Féin Assembly member Mitchel McLaughlin is challenging Mr Durkan for John Hume's seat.
At present the UUP holds five Westminster seats and the DUP has targeted each one.
Sinn Féin is confident it can take Séamus Mallon's old seat in Newry-Armagh and believes it has a good chance in Foyle, as well as a reasonable opportunity to take Eddie McGrady's SDLP seat in South Down where its candidate is Caitríona Ruane.
In Britain, Conservative leader Michael Howard and Liberal Democrat leader Charles Kennedy pre-empted Mr Blair's announcement yesterday, launching themselves on nationwide tours of key constituencies. Both were boosted on the first day of the campaign proper - Mr Kennedy by the defection of Labour's candidate in Ribble Valley and Mr Howard by an opinion poll suggesting a five-point Conservative lead among those "certain to vote".
Three other polls fuelled headline suggestions of a Tory surge, with Labour's previous lead variously being cut to between 2 and 5 percentage points.
However, while the Conservatives appeared to be closing the gap, the Populus poll for the London Times made clear that even with a 37-35 gap, Labour might have a Commons majority of 100 seats, down from its present 161, because the electoral system concentrates Labour voters more effectively.
With Scotland's representation being reduced following devolution, there will be 646 seats in the new House of Commons.
This means Labour would have to lose more than 80 seats to lose its majority, while the Conservatives would need to gain 158 to win outright.