aLEX Salmond didn't get a bet on. around Christmas time, when Labour was flying high in the polls, the SNP was 5-1 against to win Thursday's Holyrood elections. Today, he is 7-1 on to get back into office by the end of the week.  "I only bet on reliable things, like horses," he concedes, when asked whether he got some cash on when the odds were good. "But the way some of my staff are smiling at the moment I have a sneaking suspicion that they did."  Mr Salmond is ending a day's campaigning with a cup of tea at his party's headquarters. There is a quiet confidence here that whatever bets were placed in the winter are set to be collected on Friday. There are the usual caveats; the party is not being complacent, will be fighting right down to the wire, and is not taking anything for granted. But - never short of confidence anyway - Mr Salmond is anticipating success.  He says he was surprised by "only the speed" of the sudden swing in the polls towards the Nationalists since the start of the campaign (the weekend's polls tightened but showed the SNP still clearly ahead of Labour). Once people began to think about the choice of government in Scotland, he always thought the SNP's support would grow.  Labour's campaign hasn't worked, he adds. Warnings that Iain Gray's party was needed "now that the Tories are back" misunderstood the nature of the campaign.  "The mistake is forgetting what the parliament is for. It ain't just a pressure group for Westminster. They seem to have forgotten that what the Scottish Parliament is for is to form a government to run Scotland." and Labour has been too negative, he adds. "a positive campaign will always beat a negative campaign. We are fighting essentially a positive campaign."  That campaign has focused heavily on the personal appeal of Mr Salmond, and of the SNP's key election pledge to maintain a council tax freeze over the next parliament. But one thing it hasn't done, say his opponents, is sell independence. and as the campaign has reached its climax, so the focus has shifted once again on to the SNP's independence strategy.  Roll back to 2003, when the SNP last lost to Labour at Holyrood, the party had a dual strategy: "Better and Best". Policies for devolution came under "better", policies under independence came under "best". This year, tellingly, its slogan is "Be Part of Better". No mention of Best.  "We lost the 2003 election," Mr Salmond replies when reminded of the change. So, the lesson he learnt was simply to negate independence as an election issue then?  "No," he replies a tad impatiently. "We make the point that independence is an issue that should be decided in a referendum." Everyone knows the party backs independence, he argues, but voters now are happy to agree that a Holyrood election isn't the place to decide on it.  "It's now an accepted part that we are not joking; we're not going to try and sneak it in when nobody's looking. This is a consistent part of the SNP's policy programme over seven years and it now has broader appeal."  That referendum, Mr Salmond acknowledges, would not happen immediately if the SNP get back in. He says the first priority would be lobbying to put "economic teeth" into the UK government's Scotland Bill which is handing Holyrood extra powers.  SPECIFICaLLY, Mr Salmond wants to get hold of corporation tax, immediate borrowing powers, and power over the Crown Estate, in order to push through his plans for renewable energy.  Mr Salmond has not said when he would like to hold a referendum, but if the Scotland Bill is his priority, presumably the referendum would come after that? "Correct, " he says.  Could you join the SNP if you didn't believe in independence? "Yes of course you can ... if you look at the membership card, it defines independence and then the furtherance of all Scottish interests. If you sign up to that then you are a member. We don't exclude people."  This kind of debate is all in the past, he infers. "all that has been swept away. We know exactly our direction of travel, we know exactly what we are doing. We know exactly what we are doing. We are doing what we think is good for Scotland and we are comfo