EDINBURGH - Scotland has voted on whether to stay within the United Kingdom or declare independence to break the 307-year-old union in a finely balanced referendum with global consequences.
Scotland's verdict on the union should be clear around breakfast time on Friday, but a YouGov poll of 1,828 voters previously polled indicated 54 per cent of Scots would back the union while 46 per cent would seek independence.
"This YouGov poll indicates the union has prevailed," YouGov research manager Laurence Janta-Lipinski told Reuters of the survey carried out on Thursday which was not an exit poll. "It looks like the union will remain intact for the time being."
Polling booths closed at 2200 BST from remote highlands and islands to the tough city estates of Glasgow with surveys suggesting Scots were almost equally divided in a vote watched closely by Britain's allies, investors and restive regions at home and abroad.
Recent opinion polls gave the "No" campaign - those in favour of remaining in the United Kingdom - a slight edge. But as many as 600,000 people undecided up to the last moment held the key.
The final poll of polls by the non-partisan "What Scotland Thinks" website, put the No campaign on 52 per cent, the Yes camp on 48. That measure has never given the independence campaign a lead despite a sharp narrowing in recent weeks.
The gap is sufficiently close that if the pollsters have got it marginally wrong, Scotland could go its own way.
Financial markets lodged a raft of late bets that Scots would reject independence, pushing the pound and Scottish-based stocks higher in the final hours of polling.
Analysts say that means there will be a far more dramatic market reaction to a "Yes" vote than if Scotland opts to stay part of the United Kingdom.
French President Francois Hollande said the vote would be decisive for Europe as well as Britain. "After half a century of building Europe, we risk entering a period of deconstruction," he said on Thursday.
Those in favour say such fears are overblown. They say Scots, not politicians in London should rule Scotland and see a bright future for an independent Scotland in Europe, a fairer society and strong ties with London.
Those opposed say a split would slow economic growth, diminish the United Kingdom's international standing, threaten the unity of other countries and tip the balance in favour of people who want Britain to leave the European Union.
Many people see the choice, which has divided families and friends but also electrified a country of 5.3 million, as one of hearts versus heads.
Tennis star Andy Murray sent a powerful last-minute message in support of the pro-independence "Yes" vote, tweeting "Let's do this".
Alex Salmond, the 59-year-old nationalist leader, told hundreds of supporters in Perth at a final rally: "This is our opportunity of a lifetime and we must seize it with both hands."
Salmond has said the Queen should stay on as Queen of Scots. She has remained above the fray, in keeping with the constitution, but said on Sunday she hoped Scots would choose "carefully".
Electoral officials said the result will be announced around sunrise on Friday when all regional votes have been submitted. But partial results will give a strong indication after the count of cities such as Glasgow are declared around 0500 BST.
With more than 486,000 voters, Glasgow is crucial. Edinburgh and Aberdeen, which with Glasgow make up nearly a quarter of the electorate, are also expected around about that time.
Some currency traders in London prepared to stay up all night to buy or sell sterling on the result.