Glenrothes by-election: It has been one of the longest by-elections in history, but for the most part it has been conducted in the shadow of other events and tomorrow voters will go to the polls barely noticed.

It has been one of the longest by-elections in history, but for the most part it has been conducted in the shadow of other events and tomorrow voters will go to the polls barely noticed amid the worldwide attention on the US elections.

But Glenrothes will leave a mark on UK politics whatever happens. Gordon Brown chose to break convention and campaign there, even sending his wife into the fray.

Alex Salmond and his deputy Nicola Sturgeon were ever-present, as the SNP sought to cap a summer which began with Glasgow East with another scalp in Fife.

As late as yesterday Labour heavyweights such as Harriet Harman and Frank Dobson arrived unheralded, while Johh Prescott will test the water of the class system in Fife today.

In an aside, Labour yesterday boasted a celebrity endorsement by Ian Rankin even though the Rebus author has admitted he always felt like an outsider in his native Cardenden.

"Everything I know about Lindsay Roy persuades me he would be an exceptional choice as MP," said the crime author. "He has strong local ties, a passion for education, and an innate sense of fairness and justice. There's no bluster with him, no flannel or front. A typical Fifer, he'd rather roll his sleeves up than offer pie in the sky."

Naturally, being a by- election, the SNP had another quote from Mr Rankin from last year on file: "I think Salmond has done a good job. By opening up various debates he seems to be in control, in command.

"By not making mischief, he's made the Labour Party do a bit of soul-searching. He has not taken easy hits at people and his ministers have also done a good job."

Labour have hammered away at SNP-led Fife Council's changes to social care charges, highlighting increases in some of the most hard-hitting leaflets imaginable.

The SNP's Peter Grant has struggled to make a complicated counter-argument that charges have fallen for most involved. He impresses on detail, but seemed too diffident to slap down his opponents when it mattered.

Ultimately, visits by celebrities or big political beasts can only make so much difference to a contest. Angus Robertson, the SNP's Westminster leader and a key party strategist, has a metaphor befitting an MP who represents in Moray, a military constituency.

"Labour think they are winning the air war," he told me a few days ago, referring to the way that by talking up the "Brown bounce" and the involvement of the Prime Minister and his wife Sarah Labour were doing well on the airwaves and in the media generally. "But it is the ground war that wins by-elections and I believe we are winning that."

Political rivals from the Tories and Liberal Democrats looked on at the weekend as SNP troops swamped Glenrothes, and they detected that this decisive victory in the "ground war" had a demoralising effect on Labour.

Labour are fighting the air war to the end and have, rightly, not given up on winning this war. Jim Murphy, the Scottish Secretary, and Iain Gray, Holyrood leader, were there again yesterday.

The Labour campaign HQ, tucked away in a corner of an industrial estate, was buzzing with around 30 people inside and a full car park.

But the SNP HQ on Markinch High Street is busy in a different way. A press officer was having to direct traffic in the street, such was the volume in and out of the former garage opposite the railway station.

Volume and turnover make the Nationalist claim of 1200 visiting activists over the three days at the weekend plausible. They claim that, in half a day, they could deliver another leaflet to every home in the constituency. The SNP also go out of their way to campaign in their weaker areas, with a policy of knocking at every home displaying a Labour poster because often there is a split vote within households.

They relish the handshake battle as well. "They spoke about Sarah Brown but we'd rather have Nicola," said one aide of the formidable efforts of the deputy leader, who since Glasgow East has become something of a by-election specialist.

Labour, in contrast, appear to have been shoring up their core vote - Cardenden and Kinglassie to the west; Wemyss, Buckhaven and Methil to the east.

If the SNP do anything in these areas, Labour will struggle to hold this seat. If Labour consolidate in these heartlands, and if there is any kind of Brown bounce, tomorrow night could see another recount.