ITV News Scotland Correspondent Peter Smith explains the significance of the vote in the Independence debate
In the Scottish election, 65 is the magic number for an overall majority at Holyrood.
That the SNP will win is not in doubt at this stage according to an STV/Ipsos MORI poll published on Wednesday.
The only question is whether they can win big enough to secure an overall majority.
One caveat to this is turnout. Scottish elections have a record of poor turnout. With us emerging from a pandemic and poor weather on the forecast, a lot of this projection could change if voters just don’t turn up.
How do the SNP think they've done as polls closed?
However, the number of confirmed voters registered for Holyrood 2021 is 4,280,785 - a record high for Scottish Parliamentary elections.
It's close to the number who registered for the independence referendum in 2014 which suggests voters are motivated.
If we see the SNP winning these specific seats from their rivals, it means we can say with some confidence that they are on course for a majority.
They don’t have to win every single one of these key swing-seats, but if they aren’t taking at least five, possibly six, of these nine then the indicators are the SNP could struggle to reach 65.
The majority of these key swing seats are expected to declare on Friday.
The key swing seats are as follows:
The tightest marginal in Scotland with just 109 votes in it!
Currently held by Jackie Baillie, Scottish Labour's deputy leader and a veteran of her party.
She has been the MSP here since Holyrood was set up in 1999 but her majority has been getting smaller and smaller. SNP’s Toni Giugliano is the contender.
2016 margin: 0.4%Swing required: 0.2%Expected to declare on Friday
Ruth Davidson’s former seat. The outgoing Scottish Tory leader is heading to the Lords and her replacement here, Scott Douglas, has a tough task to hold the seat.
He is up against Angus Robertson, former SNP leader at Westminster who lost his seat as an MP in 2017.
Worth noting that Robertson is seen by many in the party as an heir to the SNP throne whenever Nicola Sturgeon decides to leave, and this would be his first step on that journey.
2016 margin: 1.7%Swing required: 0.85%Expected to declare on Friday
AyrJohn Scott is the incumbent here for Scottish Tories. SNP’s Siobhian Brown is the main challenger.
2016 margin: 2%Swing required: 1%Expected to declare on Friday
Alexander Burnett is seeking re-election for the Scottish Tories here.
His main challenger is Fergus Mutch of the SNP - the party’s former head of communications so a face well-known to the Scottish media.
2016 margin: 2.6%Swing required: 1.3%Expected to declare on Saturday
Daniel Johnson is the incumbent for Labour here, with the SNP’s Catriona MacDonald breathing down his neck.
She failed to be elected here in the 2019 General Election and there has been a lot of work in this constituency in particular trying to organise tactical voting for Labour - this is Unionists who prioritise stopping the SNP at all costs.
2016 margin: 2.9%Swing required: 1.45%Expected to declare on Friday
Former Scottish Labour leader Iain Gray is standing down in this seat after 14 years as the MSP.
Labour has held the seat since the first Scottish Parliament election in 1999.
Taking over the Labour mantle is primary teacher Martin Whitfield, who represented East Lothian at Westminster from 2017 until 2019.
The SNP candidate is Paul McLennan, a councillor for 14 years and a former council leader.
2016 margin: 3%Swing required: 1.5%Expected to declare on Friday
Oliver Mundell won the seat for the Scottish Tories from Labour in 2016. He is the son of former Scotland Secretary David Mundell.
His main challenger is now the SNP’s Joan McAlpine.
On the independence question, border issues are a profound concern here and it’s a staunchly pro-Union area so winning for the SNP will be a big challenge.
They won’t worry too much if they don’t win here but if they do take Dumfriesshire then that’s a significant victory.
2016 margin: 3.4%Swing required: 1.7%Expected to declare on Saturday, though a local journalist is telling me they won’t be surprised if it’s Friday.
Galloway & West Dumfries
Finlay Carson is the Scottish Tory incumbent with the SNP’s Emma Harper trying to take the seat.
Similar to Dumfriesshire, the border issues are a concern in this constituency and will hinder the SNP’s challenger who has made some pretty spectacular blunders on TV, such as suggesting a border between Scotland and England could be a good thing if it creates jobs for border guards.
2016 margin: 4.5%Swing required: 2.25%Expected to declare on Saturday
Former Scottish Conservatives leader Jackson Carlaw is trying to retain the seat he won in 2016 with a 1,611 majority.
The SNP claimed second place last time around and this time they are represented by Councillor Colm Merrick.
2016 margin: 4.5%Swing required: 2.25%Expected to declare on Friday
Some SNP-held seats to watch as an indicator of how well they are going to do:
Perthshire South & Kinross-shire
The SNP seat with the slimmest of majorities, previously held by Roseanna Cunningham. She is now standing down after 22 years in Holyrood and being replaced by with sheep farmer Jim Fairlie.
The SNP aren’t expected to lose but if she does then that’s a big red flag for Team Sturgeon - and it is the number one target seat for the Tories with Liz Smith their candidate.
2016 margin: 4%Swing required: 2%Expected to declare on Saturday
It was once held by Labour, then Tories, then the SNP won it in 2011. They have held it ever since.
2016 margin: 7.3%Swing required: 3.65%Expected to declare on Saturday
These seats will be a useful indicator as to how well the SNP are doing in their mission for a majority.
However, it is worth being aware that even if the SNP falls just short of 65 seats on their own, all polling predicts the Scottish Parliament will almost certainly still have a ‘pro-independence majority’ after this election.
The SNP would simply be supported by the Scottish Greens - as they have been in the last parliamentary term - and since the Greens are expecting to have their best ever result it would be a fairly comprehensive majority.
There is also a very slim possibility of Alex Salmond’s Alba Party winning a few seats, but that is unlikely.
And even if that did happen, Sturgeon would not be beholden to her former mentor.
But Salmond will not be a king/queen-maker in the way he hoped to be, and it’s probable that his party will actually fail to win a single seat.
Naturally, Sturgeon wants to win an outright majority of her own for the SNP.
It makes governing easier but crucially it would strengthen her hand going to Downing Street requesting a Section 30 to hold another referendum.
However, she has hedged her bets since the start of the campaign saying even a pro-independence majority at Holyrood would be enough to secure a parliamentary mandate for that second independence referendum - ultimately she believes it is a question for the Scottish Parliament and not Westminster.
So, SNP majority or not, it is almost a certainty that the Scottish independence issue will be hanging over the whole of the UK after this election.
The question then becomes “when” and “how” Scotland should hold such a vote if, as we expect, the Prime Minister continues saying no.
Don’t expect this to move quickly, though: the SNP and the Greens are both in agreement that Covid recovery should be the priority.
For that reason, it is unlikely the PM will be opening a letter from Nicola Sturgeon on Monday morning.
Instead, expect the First Minister to be very visible in putting Covid briefings first and saying the independence question needs to be answered in the next few years but, to quote Theresa May, "Now is not the time".