Alex Salmond has said the independence vote is a "once in a generation" opportunity as he pledged not to quickly bring back another referendum if Scots choose to remain in the UK.
Commentators have been predicting a "neverendum" if the No campaign wins on Thursday by a narrow margin, with nationalists calling for a new independence poll within a few years.
As a series of polls indicate the vote remains too close to call, Mr Salmond was asked if he could pledge not to bring back another referendum if the Yes campaign does not win on Thursday, he said: "That's my view. My view is this is a once in a generation, perhaps even a once in a lifetime, opportunity for Scotland."
He added: "Harold Wilson famously (said) one vote is enough in a referendum but we're not aiming to win by one vote, we're aiming to achieve a substantial majority if we can."
"If you remember that previous constitutional referendum in Scotland - there was one in 1979 and then the next one was 1997. That's what I mean by a political generation.
"In my opinion, and it is just my opinion, this is a once in a generation opportunity for Scotland."
Scotland's first minister said one vote would be enough to win, but insisted the Yes campaign was hoping for a "substantial majority".
He said that work was already under way to assemble a team of specialists to negotiate terms with the rest of the UK in the event of a vote for independence.
Several new polls show a slim lead for the No camp, with one suggesting the pro-independence side had a lead of eight points - the reverse of the picture in a poll commissioned by Better Together.
No leads by 50.6% to 49.4%, according to Panelbase for the Sunday Times and - with undecideds taken out - by 53% to 47% in research by Opinium for the Observer.
An ICM poll for the Sunday Telegraph put the Yes camp in front by 54% to 46%, although it had a smaller than usual sample size of 705.
And a Survation poll commissioned by Better Together found that 54% plan to vote No while 46% intend to say Yes, factoring out undecided voters.
Mr Salmond said that following a Yes vote there would be "urgent business" to bring the country together.
He said: "Firstly it will be a day of celebration, Scotland will have achieved something astonishing in democratic politics.
"The first and urgent business is to bring Scotland together, because on Friday after a Yes vote there will cease to be a Yes campaign and a No campaign, there will be a Team Scotland.
"I've said very clearly that I want into that Team Scotland as many voices as possible, people who have got something to offer and contribute.
"We need and have recruited specialists in a variety of fields, some extraordinary people with great things to contribute. Nobody has said no incidentally."
Mr Salmond said he would be happy to include political opponents in the campaign in such a team, including former Prime Minister Gordon Brown and Better Together leader Alistair Darling, and claimed Scottish Secretary Alistair Carmichael and Scottish Labour leader Johann Lamont had indicated they would join.
Speaking on the Andrew Marr Show, Mr Darling said he did not accept that Scotland was on a path to full independence sooner or later, regardless of what happens in the referendum.
He said: "The one point that I do agree with Alex Salmond is that I think on Thursday we've got to decide this for a generation. I don't know of anybody who actually wants to go through another two-and-a-half year referendum."
The Labour former chancellor said he personally had felt "menaced" in the campaign and had been shouted down simply for appearing at an event.
He said: "I've been involved in political campaigning for about 35 years and I've never seen anything like this before.
"I think the majority of people, the quiet majority who are beginning to speak out are not prepared to be bullied into accepting there's only one side here."
Mr Darling denied there had been a lack of passion on the side of the No campaign and accused Mr Salmond of "jumping the gun" with his comments.
"People in Scotland have yet to cast their votes, we've yet to reach this verdict," he said.
"I've said before this is going to go down to the wire but I think we will win because I don't think Scotland is going to get bullied into accepting something that it doesn't want.
"Very often when you listen to Alex Salmond talking it is almost like a contest between us and the rest of the UK, it isn't. Increasingly it looks like Salmond versus Scotland and I'll tell you what, Scotland's going to win."
Mr Darling insisted there would be a deal between the pro-union parties on new powers for the Scottish Parliament in the event of a No vote because the differences between their positions were "very small".
He said: "It's a clear choice now. We can have faster, safer and better change, reform, so that we can strengthen the health service, we can safeguard jobs, but you don't have the risks that come with independence - to jobs, to the funding of pensions and the health service, the uncertainty about currency."
He said: "I don't want to see my country subjected to years of uncertainty with all the risks.
"Five days before we go to the polls we simply don't know the answers to fundamental questions on jobs, pensions, the health service, currency and prices. We just don't know."
The two men later appeared side by side on the sofa, with Mr Salmond saying there were "idiots" on both sides of the campaign but they were a "microcosm", while the vast majority had been taking part in an "invigorating, empowering, enjoyable" debate.
He said: "I've seen nothing like this in Western Europe, certainly in recent generations."
The First Minister praised his opponent as a "first-rate politician" who would be a welcome addition to Team Scotland in the event of a Yes vote, while Mr Darling said the two men had a "high-regard" for each other and "would always get on".