Yes Scotland chairman Dennis Canavan has called on unregistered voters - the so-called 'missing million' - to help deliver cast-iron protection for Scotland's NHS with a Yes vote on September 18.
The future of Scotland's NHS has moved centre stage in the referendum debate after Labour Shadow Health Secretary at Westminster, Andy Burnham, warned that the UK Government's privatisation agenda would 'push the NHS off the cliff-edge' in the next five years.
In a speech in Manchester, Mr Burnham said analysis showed,"... that NHS forced privatisation is entering new territory and becoming harder to reverse."
However the Labour MP, who helped push through increasing privatisation south of the border when his party were in power, only called for a pause in current Tory privatisation plans until after the next general election.
Speaking during a campaign visit to Pollok in Glasgow, former Labour MP Mr Canavan, said the referendum was an opportunity to protect the Scottish NHS.
He said those who are not registered to vote or do not normally vote had a vital role to play in deciding Scotland's future - and the protection of Scotland's cherished public health service.
Mr Canavan said: "The National Health Service was founded in 1948 by an Act of the Westminster Parliament, but it is now becoming increasingly apparent that the NHS is no longer safe in Westminster's hands.
"The NHS was founded on the basic principles that it should be the property of the people and freely available to the people at the point of need. Those principles have now been abandoned at Westminster with people in England now having to pay prescription charges of over £8 per item and more and more services being privatised and therefore dependent on market forces rather than need.
"The Scottish Parliament has so far helped to protect the NHS in Scotland, but it would be naive to imagine that this will continue indefinitely under current arrangements.
"With Scotland's budget at present decided by Westminster, cuts to NHS spending in England as a result of privatisation will automatically means cuts for Scotland too.
"The trade union, Unite, is already warning of more direct charges for health services south of the border, and Westminster plans already factor in £1 billion of privatisation "savings" as they are described - which means cuts to Scotland's budget.
"The only way we can guarantee that Westminster health privatisation won't have a damaging knock on impact on Scotland's budget and Scotland's NHS is to vote Yes. It's only by taking decisions on our budget out of the hands of Westminster that we can deliver the cast-iron protection that people in Scotland demand for their health service.
"Our NHS is far too important to leave its future in the hands of voters in marginal seats in the south of England. That's a strategy based on little more than keeping our fingers crossed. The NHS needs a stronger safeguard.'
Mr Canavan added: "For all those who have never voted, or who haven't seen a reason to vote for years, now is the time to make sure your voice is heard, because Scotland needs you to protect our NHS.
"We need a Yes to give Scotland's health service an absolute guarantee. Anything less is not good enough, and presents too big a risk for a service that is at the very heart of Scottish society.
"Only a Yes vote ensures that Westminster health privatisation can't and won't damage Scotland's NHS. Under current UK arrangements, cuts in English health spending would mean cuts to Scotland's funding. Voting No could therefore threaten the very existence of the NHS in Scotland as we know it. That's a risk too far and a risk I know the people of Scotland will not want us to take.Only with the full powers of independence can our protection of our health service be guaranteed."
Mr Canavan's comments were supported by NHS for Yes. Co-founder of the pro-independence group, Dr Willie Wilson, said: "Protection of our public health service is vital for all in Scotland, but none more so than people from less well-off and impoverished areas where many of the 'missing million' voters live.
"Independence offers us a unique chance to secure Scotland's health service - to protect it from future Westminster funding cuts, and the damaging impact of privatisation south of the border.
"We are fortunate that health is already devolved to the Scottish Parliament, and it is a shining example of self-government for Scotland demonstrably being far better than Westminster government. But devolution is not enough.
"Privatisation and commercialisation are now rampant in the health service south of the border. This means that competitive tendering is now compulsory and GPs are obliged to consider which hospital offers the best deal rather than which will give the best outcome for patients."
Cuts to the NHS in England have an impact on the Scottish NHS which due to cuts to the Scottish budget.
However, speaking on behalf of the No campaign, Scottish Labour MSP Jackie Baillie claimed privatisation south of the border would not affect the NHS in Scotland which she said had been subsidised by the rest of the UK.
Responding, Ms Baillie, said: "Dennis Canavan should apologise for deliberately trying to scare and mislead Scots. As a former MSP he knows that decisions about the health service in Scotland are taken here in Scotland.
"That's what is great about devolution - we decide what happens to our NHS in Scotland, and the investment is paid for by taxpayers across the whole of the UK. It's the best of both worlds.
"The independent experts at the Institute for Fiscal Studies have made very clear that if we leave the UK our public services would be faced with cuts of up to £6 billion in the first few years. Independence would put our NHS at risk, which is why we should say no thanks in September."