A THIRD of voters may be up for grabs with six weeks to go until September 18, prompting claims from both sides that it is still all to play for in the referendum campaign.

Amid the cut and thrust of Tuesday's independence debate between Alex Salmond and No campaign leader Alistair Darling, there was an Ipsos MORI poll which became largely forgotten during the aftermath of the bitter encounter.

This poll was good for Better Together, giving a figure once undecided voters were stripped out, of 58 per cent for the Union, with 42 per cent against.

However, another set of questions and answers painted a less certain picture in the run up to the vote for Scotland's future on September 18.

A total of 19 people told the pollsters said they may not vote, with a further five per cent admitting they planned to do so, but had not yet made up their minds. There were also another section of voters who stated a preference but expressed their willingness to change their vote.

That made the number of votes still up for grabs 33 per cent, a far higher figure than usually indicated as an undecided vote.

Earlier this week, Deputy First Minister Nicola Sturgeon said that previously, had the Yes been within a small percentage margin of victory within six weeks of the poll, it would have been seized upon with glee.

The Ipsos MORI poll, commissioned by STV this week to tee up the Salmond versus Darling debate, ended up being largely forgotten in the aftermath of the debate itself. The headline figures of 54 per cent No over 40 per cent Yes, with just seven per cent undecided, appeared good for the No campaign. But a closer scrutiny of those either undecided or potential switchers showed a much more fluid position.

Blair Jenkins, chief executive of Yes Scotland: "The referendum is all to play for, and this finding reflects that a very large number of people are still making up their minds.

"Our experience is that as people engage with the issues - the opportunity to make the wealth of Scotland work for all the people, always get the government we vote for, and protect the NHS - most people decide to vote Yes.

"That was indicated by the snap poll after the debate, which found that undecideds thought that Alex Salmond won by some three-to-one."

A Better Together spokesman said: "Every poll has shown that the majority of Scots favour Scotland remaining part of the UK but we are not complacent. We will be doing everything we can between now and Sep- tember 18 to make the positive case for Scotland staying in the UK.

"We can have the best of both worlds for Scotland - our strong Scottish Parliament, with more powers for Scotland guaranteed, backed up by the strength, security and stability of being part of the larger UK."

The Ipsos MORI poll had other good news for the No camp, in that it showed their voters to be less inclined to change their mind. IN all, 85 per cent were "definitely decided" compared to 80 per cent who were certain on the Yes to independence side.

The poll was broadly good for Better Together, showing a continued strong lead and contradicting a poll last weekend by Survation for a national newspaper which put Yes within touching distance of potential victory at 47 per cent once the don't knows were excluded.

lA campaign network, Women For wIndependence, is to target female shoppers out and about in Glasgow city centre today. The organisation says women have become disenfranchised from politics and form part of about one million people who do not participate on elections north of the Border.