WITHIN a couple of hours of the doors at the Edinburgh International Conference Centre opening yesterday, a long queue had formed as party members waited patiently to get into the Scottish Conservatives' conference.

For most, this will have been a unique experience. Indeed, for those of us who have reported from the sepulchral Tory get-togethers of recent years, it was something of story.

Wasn't it only last summer when protestors outside the Albert Halls in Stirling comfortably outnumbered party members inside the venue? Going back a couple of years, Prime Minister David Cameron must still cringe when he remembers the sparse crowd of pensioners, corralled into small corner of a draughty sports hall, he addressed in Perth. And then there were all those conferences in Troon organised, with little attempt to disguise the fact, around a round of golf for party bigwigs.

This year things feel different. As the spring conference season gets underway the Scottish Tories have a spring in their step.

There are some genuinely encouraging signs for a party that, only a couple of years ago, considered winding itself up and starting again from scratch. An impressive new chairman, the QC Richard Keen, has been appointed. At Holyrood, senior MSPs like Murdo Fraser and Gavin Brown have found a new lease of life. Opinion polls are also encouraging (or at least not discouraging) with Ipsos MORI last week suggesting that 17% of Scots planned to vote Tory at the next Holyrood election. The party's share of the vote has risen in 11 successive council and Holyrood by-elections, its best run for 40 years. In places like Govan that means the vote has gone from the infinitesimally small to the merely tiny, but it's enough to persuade true blues that some sort of momentum is building.

Perhaps most importantly, Ruth Davidson has finally established herself as a strong and confident leader. In charge since 2011, it has taken her a long time to impose herself after some faltering early performances during First Minister's Questions and persistent rumours about a possible challenge to her leadership. Now, though, she heads a united party and is seen as increasingly effective in the Holyrood chambers and on television. So, this weekend, more than 1000 party members seem really quite excited to find themselves together in a grand venue where Union Flags flutter endlessly on giant multi-screen TVs.

There can be little doubt that the referendum campaign lies behind the upbeat mood. In contrast to Labour, who are uncomfortable with the constitutional debate and would rather it simply went away, the Conservatives have no qualms about draping themselves in red, white and blue and belting out a chorus of Rule Britannia. As one strategist put it: "For once we are on the side of majority public opinion in Scotland."

The point was acknowledged yesterday by Ms Davidson. Writing on the Conservative Home website, she said the referendum "has given us the chance to re-engage with people we haven't been connecting to for far, far too long." There is genuine surprise, as well as pride, that some 80,000 people (many times the Tory Party membership in Scotland) have signed up for the Conservative Friends of the Union campaign. The question, though, is whether all the encouraging signs can be turned into votes.

The Tories are beginning to believe they can. Social attitudes surveys suggest more Scots are in tune with Tory sentiments on welfare, crime, immigration, the role of the EU, and a host of other issues than election results would have you believe. "There are too many people of a right-of-centre mindset whom we are not reaching," an insider said. "If that's what people support, they have to put an X in the box with our name on it. Ruth will be quite assertive about that."

She will have to be assertive to overcome the Tories' "toxic" reputation, so carefully nurtured by Labour and the SNP down the years, but the party is confident that, as a new kind of Conservative, she has a better chance than her predecessors. They also feel a return to old-fashioned, right-versus-left politics after a No vote in the referendum would help their cause. Only time and the Westminster and Holyrood elections of 2015 and 2016 will tell, but the Scots Tories are looking in better shape than they have for years