Winner in 2019 of predecessor seat of Dunfermline and West Fife: Douglas Chapman (SNP)

DUNFERMLINE and Dollar is for the most part a successor seat to Dunfermline and West Fife, which bears a heavy burden as the constituency that first unleashed Willie Rennie on to an unsuspecting world.

In 2006, Rennie was the ­LibDem candidate in a ­parliamentary by-election that was expected to be a routine hold for ­Labour in a heartland constituency that neighboured Gordon Brown’s.

The LibDems grabbed a ­sensational victory on a 16.5% swing, which proved to be a springboard to their even more remarkable win in the equivalent Holyrood constituency of Dunfermline West in 2007, the year when other similar ­constituencies were moving to the SNP and ­helping to elect Alex Salmond (below) as First ­Minister for the first time.

Almost 20 years on, though, there is very little trace left of the ­period when voting LibDem was all the rage in places like Rosyth and ­Dunfermline. It’s almost as if none of it ever ­happened.

The party took just 8% of the ­local vote in the 2019 General ­Election, which was actually a touch below its national Scottish vote share of 9.5%. That’s perhaps testament to how fundamentally Scottish ­politics has changed over the past two ­decades, and more specifically to a succession of fateful strategic ­choices the ­LibDems took which had the side-effect of ghettoising their ­Scottish support in a few localities and ­putting other areas like Dunfermline out of reach for them.

Traditionally left-leaning ­Scottish constituencies may have been ­susceptible to the charms of the ­centre-left version of the LibDems led by Scots like Charles Kennedy and Menzies Campbell, but the centre-right party of Nick Clegg that ­happily marched into coalition with the ­Conservatives in 2010 was a ­different proposition.

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Another important factor is that more than 67% of the population of Dunfermline and Dollar have an ­exclusively Scottish national identity – a little higher than the Scotland-wide figure.

Many of the traditional Labour ­voters who switched to Rennie in the 2006 by-election will have gone on to enthusiastically vote Yes to ­independence in 2014, and will have been bemused and alienated by the LibDems’ descent into hardline ­British nationalism during and ­after the independence referendum, including a spell when the Scottish branch of the party was led by ­Rennie himself.

It’s highly doubtful that the ­constituency’s voters would even take the LibDems seriously as a ­suitable repository for protest votes in a ­by-election these days.

That leaves what used to be a ­constituency with atypical voting trends as a very familiar-looking SNP-Labour battleground in the present day.

Douglas Chapman has held the seat for the SNP for the last nine years, with huge majorities over ­Labour in both 2015 and 2019, but a tiny ­majority of just 1.6% in the much more competitive 2017 ­General ­Election.

That’s a warning sign for Naz Anis-Miah, who is replacing Chapman as the SNP ­candidate this year, because opinion polls suggest Labour are currently faring ­significantly better across ­Scotland than they were in 2017.

An almost random addition to the mix this time is the affluent ­Clackmannanshire town of ­Dollar, which sticks out like a sore thumb ­within the new seat both ­geographically and politically.

The constituency has a ­fairly ­natural-looking shape until it ­suddenly juts out northwards to take in Dollar, part of a local government ward that actually voted Tory in the 2022 local elections.

That sets it apart from the other wards in the constituency, all of which voted SNP in 2022, with ­Labour in second place in all but one.

READ MORE: Labour could grab a win in Kirkcaldy and Cowdenbeath if indy vote splits

It’s hard to escape the ­impression that the Boundary Commission just didn’t know what else to do with ­Dollar, because it didn’t have enough room for it in the ­constituencies it would have had a more natural affinity with.

However, even in Dollar the Tory vote is likely to drop this year, so the SNP-Labour tussle won’t be ­complicated much by the town’s ­involvement.

On a uniform swing, Labour would gain the Dunfermline and Dollar ­constituency even if they are as much as five percentage points ­behind ­nationally. That means the local SNP campaign may need to ­significantly outperform national trends if a ­successful defence is to be mounted.