Voters are going to the polls today in the by-election to choose a replacement for Dunfermline MSP Bill Walker, who is now behind bars after being found guilty of 23 domestic abuse charges.
But as the ballot boxes are emptied and the votes counted tonight, there is more at stake than who takes over the seat vacated by a man who should arguably never have been anywhere near being a member of the Scottish Parliament.
The SNP – the party under whose banner Walker was elected at the last Holyrood election in 2011 – is desperate for victory so it can claim endorsement for its independence drive in the run-up to next year’s referendum.
Triumph in Dunfermline would help give momentum to what looks to many people like a flagging campaign.
But winning the by-election is equally important for Labour, which used to think of Dunfermline as home turf and now needs to prove to voters it has put the 2011 Holyrood election defeat behind it and is on the road back.
Walker won the seat last time with a majority of just 590 over Labour, which means Labour needs a swing of just one per cent to win.
Every other by-election since the Scottish Parliament was established has seen some swing from the government to the opposition.
So if Labour cannot win a mid-term contest in such a seat and against a party whose previous standard-bearer has been exposed as a serial wife-beater, the question is: when can the party win?
Both the SNP and Labour selected female candidates for Dunfermline after calls from leading activists for the parties to “make a strong statement about the place of women in our society” in the wake of Walker’s conviction.
SNP candidate Shirley-Anne Somerville, a former Lothian MSP, was the clear frontrunner for the party’s nomination from an early stage.
Former Edinburgh City Council leader Ewan Aitken made a bid to become Labour’s choice, having grown up in Dunfermline, but the mood was clearly for a woman candidate. The party plumped for Cara Hilton, a Fife councillor, whose mother, Cathy Peattie, was a Labour MSP for Falkirk.
The campaign has been dominated by a row over proposed primary school closures in the constituency, but wider issues have been aired too – including the supposed threat which independence would pose to the nearby Rosyth dockyard, and Labour’s attack on the “something for nothing society” allegedly represented by free care for the elderly, free tuition, free bus passes and free prescriptions.
And, of course, the circumstances which caused the by-election could not be ignored altogether. The SNP has faced calls to apologise amid claims it did not do enough to investigate Walker’s past after it emerged a relative of one victim presented evidence of his abusive background to Nicola Sturgeon’s office.
The SNP has been talking down its chances of winning tomorrow – “a tall order” according to one senior source – and saying Labour would normally have expected the contest to be over before it had started, whereas it has been a hard-fought campaign.
Whoever wins, the Dunfermline result could prove a turning point for the fortunes of both Labour and the SNP at a crucial moment in Scotland’s politics.
We should know either way soon after 1am.