A very different group of politicians will be representing Scotland in the House of Commons after this year's General Election - regardless of how people vote.

With boundary changes too, Scotland will have a couple of fewer representatives with the number falling from 59 to 57.

Nine SNP MPs are standing down including the party's former leader at Westminster Ian Blackford, its current deputy leader there Mhairi Black, and its former deputy leader Stewart Hosie.

READ MORE: The SNP election launch and dangers of pleading to Yes supporters

Among the Conservatives, Scottish Secretary Alister Jack and Scottish Tory leader Douglas Ross are also are exiting with the former expected to take a seat in the House of Lords and the latter to focus on his work in Holyrood.

But besides those voluntarily deciding to go, many others are facing a tough fight to hold onto their seats.

Opinion surveys have suggested that a major shift will take place in Scotland's political landscape come polling day.

The Herald: Scottish Conservative leader Douglas Ross is standing down from Westminster at the General Election. Photo PA.

Research published last week by YouGov of 14,000 people forecast that Labour will sweep to power across the UK, winning a total of 385 seats while the Tories lose more than half their current MPs, slumping to just 169. The 11.5% swing to Labour would give Sir Keir Starmer an overall majority of 120.

In Scotland the poll, which was carried out from December 12 last year to January 4 this year, suggested the SNP would lose almost half their seats (down 18 to 25), just one ahead of Labour which would take 24.

Particularly worrying for the SNP, the super poll found that across Glasgow and large parts of the central belt, voters were set to switch to Labour.

READ MORE: Long read: SNP woes and Tory strife aid Labour revival

As well as the two seats the party already holds – Edinburgh South and Rutherglen – it is set to take a further 22 from the SNP. Most of these are in its old central belt heartlands, with a clean sweep predicted in Glasgow.

If the poll was replicated at the General Election, it would mean that the SNP would lose some of its most senior politicians.

Alison Thewliss, the party's home affairs spokeswoman at Westminster and its former Treasury spokeswoman, who is standing in Glasgow North, would not be re-elected.

READ MORE: Poll: Labour increase lead over SNP in shock survey of Scottish voters

Out too would be Stewart McDonald, the party's former shadow defence secretary, who represents Glasgow South, and David Linden, who is standing in Glasgow East. Mr Linden is a key ally of Westminster party leader Stephen Flynn.

The YouGov poll also pointed to Labour taking Na h-Eileanan an Iar, which is currently held by former SNP MP Angus Brendan MacNeil who now sits as an independent.

The Herald: Angus MacNeil said he would not be rejoining the SNP group at WestminsterFormer SNP MP Angus Brendan MacNeil, who now sits as an independent, is facing a challenge from both the SNP and Labout in Na h-Eileanan an Iar.  Photo PA.

It also suggested that Kenny MacAskill and Neale Hanvey would be out with Alba losing its two MPs in East Lothian and Kirkcaldy respectively to Labour.

Launching the SNP's general election campaign in Glasgow this month, First Minister Humza Yousaf vowed to voters that his party would help remove the Conservatives from Scotland.

The Tories currently have seven MPs and the YouGov poll suggested Mr Yousaf would have some success with his goal.

It pointed to nuclear minister Andrew Bowie being replaced by the SNP in his West Aberdeenshire and Kincardine, while Mr Jack's seat of Dumfries and Galloway would switch to the SNP should the poll be replicated on election day.

READ MORE: Why does the SNP still lead the polls after many months of troubles?

SNP defector Lisa Cameron, who joined the Scottish Tory group in Westminster last October, would also be ousted according to the YouGov poll with her rebranded seat of East Kilbride & Strathaven seat going to Labour.

Elsewhere in Lanarkshire, the You Gov poll pointed to the SNP's Steven Bonnar, Anum Qaisar and Marion Fellows, all being ousted at the general election (in Coatbridge and Bellshill, Airdrie and Shotts, and Motherwell and Wishaw respectivel), with their three seats being won by Labour.

The poll suggested the SNP MP Stuart McDonald would be re-elected to hold Cumbernauld and Kilsyth in a rare central belt hold for the party.

A close look at the numbers reveals how much of a knife-edge this election result is on. In three constituencies, the SNP and Labour sit on roughly the same share of a vote.

In Dunfermline and Dollar, the two parties are predicted to get 34% of the vote apiece; in Edinburgh North and Leith it’s 33%; and in Livingston it’s also 33%. YouGov’s analysis hands the first of those three to Labour, but the latter two to the SNP.

Then there’s numerous other seats which are also very close. The Tories would only win both Aberdeenshire North & Moray East and Gordon & Buchan by a single percentage point (28% to the SNP’s 27), while Dumfries & Galloway would go SNP only by a single percentage point too (27% to the Tory’s 26).

There’s also a few three-horse races. Former Scottish secretary David Mundell would keep his Dumfries, Clydesdale & Tweeddale seat – which he’s held since 2005 – with 28% of the vote. But hot on his tail is the SNP (25%) and Labour (24%).

Mid Dunbartonshire – which is replacing East Dunbartonshire – is a three-way race between the Labour (27%), the SNP (25%) and the Lib Dems (23%). The predecessor seat was of course held by Scottish Lib Dem leader Jo Swinson from 2005 to 2015, and from 2017 to 2019, when she lost to the SNP's Amy Callaghan. With a narrow majority of 149 Ms Callaghan is likely to face a tough challenge to hold onto her seat.

The Herald: The SNP MP Amy Callaghan will face a tough contest in Mid Dunbartonshire. Photo PA.

North East Fife – the constituency won by the SNP in 2017 by two votes, before being lost in 2019 to the Lib Dems is set to return the Lib Dems again with a decent lead with Wendy Chamberlain retaking her seat. But with the SNP and Labour both eyeing it up, this could be closer than YouGov suggests.

The poll also suggested Labour look set to comfortably hold Ian Murray’s Edinburgh South and Michael Shanks’ Rutherglen,  while Lib Dems will easily retain Alastair Carmichael’s Orkney & Shetland and Christine Jardine’s Edinburgh West.

Of course, as the political parties point out, this is just one poll and the only poll that matters is the one that takes place on polling day itself.

As the moment, it's not actually known when that will happen.

The Herald: First Minister Humza Yousaf is to hold a climate change summit with Holyrood party leadersThe next General Election will be critical to Humza Yousaf's future as SNP leader and First Minister. Photo PA.

Earlier this month Prime Minister Rishi Sunak said he is working on the assumption that he will hold a general election "in the second half of this year".

Former Chancellor George Osborne, an ally of Mr Sunak, last week predicted it would be held on November 14.

But of course, even if the Prime Minister is working towards this timetable, he could change his mind if he believes circumstances may favour a different date.

In Scotland, all eyes will be on the fortunes of the SNP, Labour and the Conservatives.

Will Labour be able to keep its momentum? Will circumstances change for the SNP to allow the party to comfortably see off the Labour challenge? Only time will tell.

It will be the first time Mr Yousaf will be leading his party into a general election. He's already set a threshold of winning a majority of seats as a mandate for negotiating with the UK Government on independence, potentially on holding a new referendum.

That means he must win 29 seats for this goal to be met, leaving it rather unclear what will happen if the SNP doesn't reach that number.

With last week's YouGov poll putting the SNP winning 25 seats, the implication would be he wouldn't be mandated on this result to seek independence or indyref2 negotiations with the UK Government.

But what then of his own position?

If the SNP did win 25 seats, it would still be the biggest party in Scotland, so Mr Yousaf could reasonably argue that his party had won the election in Scotland and he should remain as leader.

But would his party be persuaded to hold onto a leader after suffering such heavy losses of 18 seats and with a Holyrood election due in May 2026?

Should the YouGov poll be replicated on polling day, this will be one of the pressing questions facing the SNP.