By Steve Bargeton, political editor

THESE ARE heady days for the SNP as they gather in Perth today for their annual conference.

Leader Alex Salmond may not actually say it when he delivers his keynote speech on Friday, but the message will be clear—“go back to your constituencies and prepare for government.”

With a little over six months to go until the Holyrood elections the Nationalists have much to be optimistic about.

They are neck-and-neck with Labour in the opinion polls, ahead in many.

More importantly they are winning elections in Labour heartlands.

The Markinch and Woodside East council by-election in Fife saw a swing to the SNP of 30%.

The result has shocked Labour to the core. This is Labour territory, next door to Gordon Brown’s constituency, and the by-election was held in the middle of a Labour Party conference.

SNP activists chappin’ the doors in the weeks up to the by-election detected what Nationalists say they are finding on doorsteps across the nation.

In traditional Labour territory voters are, in the words of one activist, “scunnered.”

Little wonder then that at a time when many parties are seeing a decline in membership numbers, the army of SNP activists is growing.

Over the last 12 months membership is up by 11% to 12,246 from 10,962 last year, and up from 10,021 in 2004.

Mr Salmond says it is time for a change.

The conference catchline in Perth this week reflects that hope. It states simply, “It’s time.”

“The people of Scotland know it’s time for a change, and only the SNP can deliver the fresh approach that people up and down our country are crying out for,” said Mr Salmond.

“Next May, voters across Scotland will have a simple choice to make about Scotland’s future.

“They need to decide between the tired and washed out Labour Party who have run out of ideas and popular support, and the positive vision for our country proposed by the SNP.

“Scotland knows it’s time for a change. This conference will help us to underline that it’s time for an SNP government next May.”

The talk among delegates in the restaurants and pubs of the Fair City this week will not be of opposition, but of a Scottish Executive led by SNP ministers, of a Nationalist First Minister, of a referendum that will take the country on the road to the dream of Scottish independence.

And they will feel with some justification that the pieces are beginning to fall into place.

Multi-millionaire Kwik Fit founder Sir Tom Farmer announced at the weekend that he is giving the SNP £100,000 to allow them to compete “on a level financial playing field” with their political opponents.

Significantly he is not a member of the SNP but wants to see a “real open debate for the future of Scotland.”

Once laughable talk of Mr Salmond becoming First Minister is commonplace.

Next month he is off to talk to the head of the civil service in Scotland, John Elvidge, to make preparations for an SNP government.

“The SNP are working hard and preparing for government, putting forward our ideas on how to take Scotland forward,” said Mr Salmond.

“Next May we want to hit the ground running, which is why we are beginning talks next month with the civil service.”

No wonder then that Nationalists gather in Perth this week full of confidence, in the real belief that 2007 can be their year.

But there is the not insignificant matter of actually winning the election in May.

Mr Salmond has set a target of winning 20 new first-past-the-post seats and the SNP will need every one of them if they are to have any chance of forming an administration.

Winning a handful of council by-elections with massive swings is one thing, taking a crop of Labour strongholds is another altogether.

The voting system for the Scottish Parliament means that it is virtually impossible for any one party to get an overall majority.

That means the SNP, even if they do very well, will have to find a partner to form an Executive.

And while the Liberal Democrats have been happy to go into coalition with Labour twice and might well do so again, they have made it clear they will have no truck with a referendum on independence.

So, the SNP meet in Perth this week full of confidence and with their prospects brighter than at any time since devolution—but with an electoral mountain still to climb.