Danny Alexander appears very relaxed for someone widely predicted to be "electoral toast" about to be "consumed by a tartan tsunami" in his Inverness, Nairn, Badenoch and Strathspey seat.

However, in the somewhat unusual setting of a picnic table in Drumnadrochit's sun-kissed car park, the Chief Secretary to the Treasury, insists he has done enough to survive since becoming the first MP from a Highland seat in decades to be in Cabinet (45 years since Argyll Tory MP Michael Noble was President of the Board of Trade).

Lord Ashcroft's poll published in February, had him trailing the SNP by 29 points, largely viewed as an insurmountable deficit despite winning over 40 per cent of the vote in 2010.

But as supporters prepare to knock on doors in the community most closely associated with Nessie, he explains, with characteristically affable confidence, why predictions of his demise are premature.

"I think the polls accurately reflect it is a battle between myself and the SNP, and that it is a close fight. But our canvassing suggests that I will make it. What the polls don't show is the respect for what I have done as a local MP, and a Highlander in the government."

He lists rural fuel discounts, investment in broadband, supporting mountain rescue teams, helping the whisky industry, a city deal for Inverness. "I think I am one of the few politicians who gets accused for doing too much for his area."

Certainly there were a few eyebrows raised with the inclusion of the likes of Carrbridge in his constituency - and only 25 miles from a 24/7 Tesco superstore - in the list of 17 mainland locations for the 5p-a-litre reduction introduced in 2012 for the islands.

"I am very proud that after decades of Labour and Tory Governments largely ignoring the Highlands, an MP for a Highland Constituency near the top of government has managed to redress the balance a wee bit."

But he does concede that some have not managed to come to terms with the LibDems entering a coalition with the Tories, although says the impact of the likes of the bedroom tax is not often raised often on the door steps.

He feels liberated in now being able to attack the Tories and thinks fair-minded people see the difference the LibDems have made.

But Drew Hendry, his SNP challenger and leader of the Highland Council, says he hasn't found too many. "There are a lot of people who say they voted LibDem before but won't be doing so again; that they hadn't voted LibDem in order to support a Tory government."

He says he is not going to talk down the things that Danny Alexander has achieved, but the feedback had been they weren't sufficient.

"Highland's housing debt is £160m. The interest and capital repayments on that each year are £17m. As council leader I wouldn't have had to contemplate any cuts at all if Danny had done something about that, or we could have but hundreds of more council houses."

(Mr Alexander says housing is a devolved matter, although his colleague Alistair Carmichael is claiming credit for securing £10 million from the UK Treasury to help tackle the Shetland Island Council's £40m worth historic housing debt.)

Drew Hendry says the welfare cuts have simply served to increase rural poverty in a low wage economy where people already struggle with heating and fuel costs.

"When they decided to roll out the bedroom tax for social housing nobody took into account that there are something like 80 Highland communities that have no one or two bedroom houses. Where were these people expected to go? Voters know the welfare reforms have come from Westminster."

Hendry moved north from Edinburgh 14 years ago bringing his digital marketing company with him. His campaign HQ in Inverness is buzzing, but his demeanour is reminiscent of the manager of his beloved Hearts, as he kept refusing to contemplate winning the Championship, when most had been predicting it was in the bag for months.

He insists: "We were third time in 2010 so there was always going to be a big job to do."

It is clear things are going well in the SNP's bid to take the LibDems' biggest Scottish scalp, and Labour candidate Mike Robb who runs his IT business from Inverness, doesn't disagree.

"It is hard work because obviously the SNP are doing really well in the polls and in the Highlands they have always been quite strong. I was the Labour candidate here in 2010 and I came second to Danny."

He says Labour's canvass returns suggest he is now running "a good second" to the SNP .

But he is sure the the LibDem vote is collapsing. He says Lib Dem voters in 2010 "are now openly saying they are not going to vote LibDem again. There is a sense of betrayal, that Danny has almost sold out for a seat at the government table. And for all his words about the Highlands what they are seeing is the bedroom tax and the VAT rise, and although tuition fees don't apply north of the border, they symbolise a pledge broken."

Meanwhile the Green, Tory, Scottish Christian and UKIP candidates have established local pedigrees.