THE anti-independence campaign has been warned it is years behind the Scottish Nationalists in terms of having a voter database that can compete with the SNP's much-heralded election machine.

According to senior Nationalists, the SNP's database system will give the pro-independence camp a huge advantage over its opponents when the independence referendum campaign gets under way.

Even if the other parties got their act together now, they would be several years behind the SNP in terms of information-gathering, it is claimed. There could also be barriers to the different parties sharing information under data protection rules, even if they put historic rivalries behind them and wished to co-operate in this way.

Knowing the whereabouts of supporters is vital to getting the vote out, and the SNP has been building up its Activate system for more than five years, giving it a huge archive of voter intelligence.

Thanks to two donations this year of around £1 million each, the party is in a healthy financial state as it looks forward to the referendum in 2014-15, but Activate gives the SNP data that would be impossible to buy.

Angus Robertson, SNP's Westminster leader and campaign chief, said: "Activate has helped SNP activists in every election from 2007 to winning a majority in 2011's Scottish Parliament elections. Built in-house, this technology is miles ahead of that being used by other parties in Scotland and will play a big part in supporting our campaign for independence."

He added: "With the opposition to independence scattered and disunited, the Unionist parties have a long way to go to bring together the technology and the message in the same way that the SNP has achieved in previous elections."

Another senior party source said ensuring Activate complied with data protection rules had been complex, and sharing information between parties may be an issue for the Unionist camp.

Activate emerged as a concept during 2005 in discussions between Mr Robertson and the party chief executive Peter Murrell on how to improve canvass returns. Drawing on the expertise of SNP members working in information technology, the party developed its own bespoke database system.

All parties are entitled by law to access Scotland's electoral roll of almost four million voters, but the SNP's rivals have not developed anything as sophisticated as Activate for building profiles. Previously, canvass returns simply recorded how people said they had voted at the last election and whether they were considering switching next time.

But Activate goes much further, fitting each voter into one of 44 consumer types identified by postcode, family type, income and age. If voters, either on the doorstep or canvassed by telephone, suggest policy areas of particular interest, that too is entered into the system.

An expression of concern about education, for example, will lead to a follow-up mailshot focusing on that issue.

The SNP has gone on to create a smartphone application which canvassers can use to enter the information straight back into the central database, meaning ebbs and flows of support can be tracked in real time.

Activate was trialled during the Westminster by-election in 2005 in Livingston and in the Holyrood seat of Moray six months later. It was fully operational in time for the 2007 Holyrood election, from which the SNP emerged as the largest party. It has since been built on through European, Westminster and council elections, adding breadth and depth to the bank of voter intelligence.

The next turning point was the Glasgow East by-election in July 2008. In many parts of the constituency the SNP had no history on the ground, so it lacked canvassing information.

But commercial market research software showed pockets of the local community in Glasgow East shared the same socio-demographics as areas in Govan or Dundee – about which Activate had lots of information. This allowed activists to flood the areas that were most promising. The only time Activate let the SNP down was in Glenrothes, where a failure to maintain the canvassing up until polling day meant it failed to detect a late surge to Labour. A week before the Holyrood election in May, HQ staff were stunned to see the political barometer hit 46% support for the SNP, within 1% of the actual result.

Where those responding to canvassers have mentioned the constitution, canvassers will now draw out the strength of support for independence, thoughts on stronger devolution and areas of doubt which will feed into the campaign to come.