A swing for independence has the rival Yes and No campaigns neck and neck ahead of next week's Scottish referendum, the latest poll has suggested. Among those who said they were certain to vote on September 18, support for independence and staying in the United Kingdom was tied on 41%, according to new research from TNS.
That means backing for Yes is up from 38% last month while support for the union is down from 46%. Tom Costley, head of TNS Scotland, said: "This poll reveals a remarkable shift in voting intentions but the signs were evident in our last couple of polls which indicated a narrowing of the No lead, especially amongst those who told us that they were certain to vote.
"It is too close to call and both sides will now be energised to make the most of the last few days of the campaign and try and persuade the undecided voters of the merits of their respective campaigns."
There could be some 600,000 voters who have still to make up their minds, with 18% saying they are certain to vote in the referendum but are still unsure how they will cast their ballot. It comes after research by YouGov at the weekend put support for Yes ahead for the first time in the campaign, with 51% backing independence and 49% preferring to remain part of the UK, when undecided voters were excluded.
Among the 990 people polled by TNS, support for No had dropped from 45% a month ago to 39% while the Yes vote increased from 32% to 38%. The number of women backing independence also appears to be rising, going from 27% to 35%, while female support for No has dropped from 49% to 41% over the period.
According to TNS, the only group where No has a strong majority is among Scots aged 55 and above, with 49% stating they want Scotland to stay in the UK compared to the 31% who back leaving.
Blair McDougall, campaign director for the pro-UK Better Together organisation, said: "The last couple of days will be seen as the moment the referendum got real. We know from these polls that there is no room for a protest vote. The vote of any one of us could be crucial and could make the difference between the UK breaking up and staying together.
"We have seen from the reaction of the international markets just how serious a risk separation poses to our pound, NHS and pensions. If we leave the UK, jobs would be at risk and the money available for spending on our NHS would be cut.
"We are working flat out to get across our positive vision for Scotland that means we don't need to take on all the risks. There is a better way to build the better nation that we all want. We can have more powers for Scotland, backed up by the strength, security and stability of being part of the larger UK.
"Separation puts that at risk, which is why we should say no thanks on September 18. This is a fight for the future of Scotland and it's one we will win."
Yes Scotland chief executive Blair Jenkins described it as a "breakthrough poll which confirms that Yes has the momentum".
He said: "Last September the No lead was 22 points - now Yes has surged to draw level at 50/50, and our campaign has the wind in its sails. Yes support is rising particularly strongly among women and Labour voters.
"Scotland is one of the wealthiest countries in the world. More and more people are beginning to realise that a Yes vote is Scotland's one opportunity to make that enormous wealth work better for everyone who lives here, create more jobs, and protect Scotland's NHS from the damaging effects of Westminster privatisation and cuts.
"The No campaign's empty talk of more powers smacks of utter panic and desperation as they lose their lead in the polls. The people of Scotland will not trust the Tories to deliver powers that fall far short of what we need. The sure fire way to achieve the full range of powers Scotland needs to build a fairer society and more prosperous economy is to vote Yes a week on Thursday.
"While the No campaign press the panic button and blame each other for a series of blunders, Yes will get on with the job of persuading more of our fellow citizens - both No and undecided voters - that we need a Yes vote to put Scotland's future in Scotland's hands."
Earlier on Monday, former prime minister Gordon Brown announced plans for a timetable to give the Scottish Parliament more powers if voters reject independence in next week's referendum. Mr Brown said a No vote would be the "starting gun" for further powers for Holyrood, with a new Scotland Act drawn up to give the country greater control over finance, welfare and taxation.