DATA received from two million people who completed the SNP’s national survey will be “gold dust” in the fight for a Yes win in a new independence referendum, a senior figure involved in the 2014 vote has said.

The strategist, who does not want to be named publicly, said the exercise would allow the party to assess the mood of the country and how views may have shifted over the last two years and in particular since the EU referendum in June.

He underlined a question where respondents were asked to rate their support for independence from one to 10, which he said would enable party bosses to identify swing voters who could be targeted by Yes canvassers in future campaigning efforts.

“Among the things Nicola Sturgeon will be looking at is where public opinion is right now,” he said.

“The most valuable thing I think is where people put themselves on that scale of one to 10. If people put themselves at one or two, then we’re not going to be able to move them.

“But people who place themselves at three, four or five are probably open to persuasion and potentially could move to support a Yes vote. Identifying those groups is gold dust to independence campaigners.”

He added: “If people put themselves in an undecided category then canvassers can go back to them, ask them what their concerns are and give information to them to address those.”

The survey, which closes on St Andrew’s Day tomorrow, was unveiled by the First Minister in September in what she called the “biggest listening exercise in Scotland’s history” and was described as the first phase of a new “summer” independence initiative that she announced at the party spring conference.

Along with the survey she announced the setting up of a growth commission to examine projections for Scotland’s economy in the post-Brexit climate and in the context of independence. The commission will also examine what currency an independent Scotland would use.

Last week weekend Sturgeon said 1.7 million people had completed the survey, which she said had “reignited grassroots activism” over the past 12 weeks, and work was on course to reach the two million target that she had set. “Across the country this weekend, our volunteers have been listening to people’s views at hundreds of street stalls and community events in a final push for responses,” she said. “At the last count, 1.7 million people had made their voices heard and we’re on track to reach our target of listening to two million people by St Andrew’s Day.”

She added: “Responses will be considered after the survey period comes to an end and I would urge anyone who hasn’t yet participated to do so before Wednesday.

“This is the biggest listening exercise in our party’s history and will undoubtedly help understand in detail how people feel now about Europe, Brexit and independence. We are determined to build, if we can, a consensus on the best way forward for our nation.”

Tommy Sheppard, the Edinburgh East MP who was a key figure in the campaign for a Yes vote in 2014, told The National: “The fact so many people have filled in the survey shows that people want to have their say and want their views heard.

“I think it’s going to be very useful when we get the results. It will allow us to see how many people who have been against independence may be changing their minds, and this is going to be a big block of people.

“It will be important to track how their opinions are changing in the context of Brexit, and this survey will allow us to do that as it asks how people voted in 2014 and in June 2016.

“We suspect a lot of people are moving from No to Yes or at least looking at the possibility of independence as a result of Brexit.”