It comes as the latest polls suggested the result remained too close to call, with a slender lead for a “No” vote.
First Minister Alex Salmond has written to voters appealing to them to back independence, urging “let’s do this”.
Key figures from the pro-Union Better Together campaign were out meeting nightworkers into Wednesday, ahead of a Love Scotland, Vote No rally.
Three new polls, one by Opinium for the Daily Telegraph, another by ICM for the Scotsman and a third by Survation for the Daily Mail, were published on Tuesday evening.
With undecided voters excluded, they all suggested a lead for “No” of 52% to 48%.
On the final day of campaigning, in a letter to the people of Scotland, Mr Salmond told them they will hold power in their hands as they vote to determine their country’s future on Thursday.
He asked voters to step back from the political arguments and statistics that have defined the two-year campaign and trust in themselves as they step into the polling booth.
Mr Salmond said: “The talking is nearly done. The campaigns will have had their say. What’s left is just us – the people who live and work here. The only people with a vote. The people who matter.
“The people who for a few precious hours during polling day hold sovereignty, power, authority in their hands. It’s the greatest most empowering moment any of us will ever have. Scotland’s future – our country in our hands.
“What to do? Only each of us knows that. For my part, I ask only this. Make this decision with a clear head and a clear conscience.”
Better Together leader Alistair Darling and former Prime Minister Gordon Brown will front a Love Scotland, Vote No rally in Glasgow later.
Ahead of that event, Scottish Labour leader Johann Lamont and leader of the Scottish Conservatives Ruth Davidson have been out campaigning overnight.
Ms Lamont, along with her deputy Anas Sarwar, was meeting print workers on the night-shift at Trinity Mirror Print Works. They were promising “better, faster, safer change” with a “No” vote.
Ms Davidson and Chief Secretary to the Treasury Danny Alexander met warehouse workers at Malcolm Distribution in Linwood.
Blair McDougall, campaign director of Better Together, said: “Unlike Alex Salmond who is on a helicopter victory tour, Better Together is campaigning through the night for a No vote.
“Better Together campaigners are working tirelessly to spread the message that there will be better, faster, safer change with a No vote for a stronger Scotland, while Alex Salmond’s political project for separation risks jobs, pensions and the NHS.”
Responding to the latest polls, Mr McDougall, from Better Together, added: “This vote will go right down to the wire. There is no room for a protest vote. If we vote to leave the UK there would be no going back, no matter what it costs us in terms of bigger cuts, higher prices and fewer jobs.
“The last week has exposed how much of a risk going it alone would be for Scotland. Jobs would move to England, funding for pensions would be cut and our NHS would be at risk.
“These are risks we just don’t need to take. We can have faster, better, stronger change for Scotland within the UK.”
Yes Scotland welcomed the latest poll findings describing them as “hugely encouraging”.
Chief executive Blair Jenkins said: “People know that a Yes vote is Scotland’s one opportunity to achieve job-creating powers, protect our NHS from the damaging impact of Westminster cuts and privatisation, and ensure that never again do we get Tory governments imposed on Scotland that we have roundly rejected.
“These polls – like all the recent polls – show that we are in touching distance of success on Thursday.
“The referendum is on a knife edge, and this will spur on everybody who wants and is working hard for a Yes to redouble their efforts.”