"Historic" is a word beloved, and much abused, by politicians. But no other adequately describes the choice the people of Scotland must make today. The polling stations beckon them to make the most momentous decision in almost 300 years of domestic politics. And when they close tonight at 10 p.m., the near-certain expectation is that they will have voted themselves a Home Rule parliament - complete with tax-varying powers.
There were fears that the suspension of the referendum campaign following the death of Princess Diana - and the subsequent outpouring of national grief - would bolster pro-Union sentiment, and damage the chances of a "Yes, Yes" vote. Some urged the government to delay until next week, when the people of Wales vote on a Welsh Assembly.
The Prime Minister appeared sanguine at the prospect of condensing the campaign for his constitutional flagship into the four days following the royal funeral. But there was nervousness still on Monday, as it became clear that Mr Blair's whistle-stop tour of Glasgow and Edinburgh would be his first and last before the vote.
For all the talk of 100 hours of frenetic campaigning, the atmosphere seemed flat, distinctly lacking in passion or prime ministerial urgency. However, Mr Blair's aides were relaxed. The Scots, said one, had been discussing this issue for 20 years and more. "Now they just want to get on with the vote." And the opinion polls appear to bear that out.
The government has always recognised the need for a decisive vote to bestow full legitimacy on the Edinburgh parliament - and to provide a much-needed boost for the "Yes" campaign in Wales, where voters in 1979 rejected devolution by a margin of four to one.
Mr Donald Dewar, the Scottish Secretary, last night forecast a higher-than-expected turnout, and a more resounding message from Scotland that the English might yet expect to hear.
If that assessment is borne out, Mr Blair will be able to say he has bowed to "the settled will of the Scottish people." As the Deputy Prime Minister, Mr John Prescott, said yesterday, that will mark a moment of the most profound significance for Scotland - and for the United Kingdom as a whole.
Where it will lead is anybody's guess. Some say Scots have the opportunity to blaze a trail for the institutional and constitutional reform necessary to the future security and integrity of the United Kingdom as a whole. Others contend that Scottish devolution will prove the precursor to conflict with Westminster, and inevitable separation.
These are not the conflicting views of "Yes" and "No" campaigners hurled across the referendum battlements. For the "Yes, Yes" campaign embraces three parties - Labour, Liberal Democrat and Scottish Nationalist - with fundamentally different views about the future of Scotland and the Union.
In a final, eve-of-poll message, Mr Blair affirmed his belief that devolution will enhance Scotland's sense of nationhood without damaging its essential Britishness. Were the proposals a stepping stone to independence, he declared, he and Mr Dewar would have nothing to do with them.
But many Labour unionists are uncomfortable to find themselves in temporary coalition with others who take a very different view. The Liberal Democrats - unlike Labour - have always openly acknowledged the validity of the "West Lothian Question", and see a federal Britain as the logical outcome of devolution. The Scottish National Party sees a Scottish parliament as the first, crucial step to fully fledged independence.
If Scotland votes Yes and Yes again tonight, Mr Dewar and Mr Alex Salmond, the SNP leader, will be united in celebration. But one or other of them, in the long run, must be proved wrong.
Mr Michael Ancram - late of the Northern Ireland Office, now Tory spokesman on constitutional affairs - has no doubt. Indeed he says his "shared analysis" with the Scots nationalists has been his inspiration in this campaign.
Focusing on Labour's Scottish local government "sleaze" factor, Mr Ancram says Scots are being asked to vote for "a potentially bigger midden, a barrel with more pork and an arena with an even greater capacity for the politics of fear." As the Scottish Parliament would raise "the tartan tax" so, he contends, local authorities would raise council taxes and business rates. The individual Scot would thus be penalised, and Scottish competitiveness damaged.
Mr Ancram contends that English taxpayers will eventually rebel against funding higher per capita spending in Scotland, post-devolution. And he says if the current block funding criteria were changed to those of a needs-based assessment, it would blow £1.5 billion out of the existing Scottish budget.
Reducing the number of Scottish MPs would be but the beginning of the erosion of the power Scots currently enjoy in the parliament and government of the UK; the office of the Secretary of State would be castrated; while "every promise unfulfilled, every encouraged hope dashed, would be laid at the door of Westminster."
That, says Mr Ancram, is the "malign scenario" at which Scots nationalists now rejoice; the dynamic for which they have lent their support; a process which will untie the knots binding the United Kingdom, "the unbundling" of that which unionists hold dear.
However, the evidence of the moment is that Scotland is not listening. His lesser problem perhaps is that he once argued the contrary case. The greater problem is that he, an MP for an English constituency, should find himself leading the charge - his every pronouncement a reminder of the electoral wipe-out which befell a Tory party perceived for so long to govern Scotland with distance and disdain.
Scottish voters today seem set to exact their revenge, ironically at a moment when Scots so predominate in the new government in London - a reminder for Mr Blair, perhaps, that settling the will of the people marks but the beginning of his great constitutional adventure.