Exclusive research for The Scottish Sun revealed the number of voters backing Britain has slumped from 57 per cent to 50 per cent in just six weeks.
And the gap between those who want to prevent its break-up and those who want independence has shrunk from 19 points to just 11.
The poll by Ipsos MORI showed outright support for a separate Scotland has risen by just one point since December to 39 per cent.
But the number of Scots who count themselves as "undecided" has more than doubled — pointing to a gradual softening in opposition to independence.
Last night SNP campaign director Angus Robertson hailed the findings as a victory for his party.
He said: "This is an excellent poll, confirming that the momentum is with the independence case.
"The common feature of every survey in recent weeks is rising support for independence, and falling opposition.
"In the four months leading up to the 2011 election, the SNP came from behind and achieved a swing of nearly 15 per cent from Labour to win.
"Now, two-and-a-half years out from the referendum, a swing of less than six per cent would see independence move ahead."
He added: "The 'Yes' campaign will be broad-based, united and positive — and I believe will be successful." The poll was conducted from January 27-29. It followed the launch of Alex Salmond's referendum plans on Burns Night. It asked 1,005 adults exactly the question the First Minister has suggested for the referendum: "Do you agree that Scotland should be an independent Country?
And the gap between those who want to prevent its break-up and those who want independence has shrunk from 19 points to just 11.
The poll by Ipsos MORI showed outright support for a separate Scotland has risen by just one point since December to 39 per cent.
But the number of Scots who count themselves as "undecided" has more than doubled — pointing to a gradual softening in opposition to independence.
Last night SNP campaign director Angus Robertson hailed the findings as a victory for his party.
He said: "This is an excellent poll, confirming that the momentum is with the independence case.
"The common feature of every survey in recent weeks is rising support for independence, and falling opposition.
"In the four months leading up to the 2011 election, the SNP came from behind and achieved a swing of nearly 15 per cent from Labour to win.
"Now, two-and-a-half years out from the referendum, a swing of less than six per cent would see independence move ahead."
He added: "The 'Yes' campaign will be broad-based, united and positive — and I believe will be successful." The poll was conducted from January 27-29. It followed the launch of Alex Salmond's referendum plans on Burns Night. It asked 1,005 adults exactly the question the First Minister has suggested for the referendum: "Do you agree that Scotland should be an independent Country?