Voters in the constituency of Rutherglen and Hamilton West are going to the polls on Thursday to elect a new MP.
The winner of the by-election will replace Margaret Ferrier as the MP for the seat, which is in South Lanarkshire in the west of Scotland.
Here, the PA news agency answers some of the key questions surrounding the ballot:
Why is the by-election taking place?
Scotland’s first recall petition for a sitting MP led to Ms Ferrier losing her seat in the House of Commons after she broke Covid laws in 2020.
A total of 11,896 voters signed the petition – passing the required threshold of 10% in the constituency, which has 81,124 registered voters.
The result of this was declared on August 1, though political parties were gearing up for a by-election campaign earlier in the summer.
What led to Margaret Ferrier being recalled?
When Ms Ferrier’s breach of coronavirus rules came to light, she was removed from the SNP and went on to sit as an independent.
She travelled from Scotland to Westminster after testing for Covid in September 2020, and even spoke in the House of Commons while waiting for the results. She then travelled by train back to Scotland once she had received her positive result.
She has been ordered to complete a 270-hour community payback order by a court after admitting culpably and recklessly exposing the public “to the risk of infection, illness and death” as a result of her behaviour.
Earlier this year, she was handed a 30-day suspension by the Commons Standards Committee, enough to allow the recall petition to go ahead.
Ms Ferrier resisted calls to step down from her seat, but she will not be running for re-election.
How is the race shaping up?
The seat was always going to be keenly fought between Labour and the SNP.
Labour took it in the 2017 general election before Ms Ferrier won it back for the SNP in 2019.
Sir Keir Starmer’s party is hopeful that a win in Rutherglen will show Labour can make gains against the SNP at the upcoming general election, paving the way for his party to return to power at Westminster. He has said the by-election is of “monumental significance”, and other Labour politicians have been talking up their chances.
Humza Yousaf and key figures in the SNP have also been to Rutherglen frequently during the run-up to the vote. With 2023 having been a turbulent year for the SNP so far, holding the seat would show it can still enjoy electoral success.
The First Minister recently said he is “hopeful” of victory on Thursday.
Polling analysts have said the data points towards a Labour win as the most likely outcome, but much will be read into the size of the majority.
Who is the SNP candidate?
Councillor Katy Loudon was chosen as the SNP’s candidate for the seat.
She has lived in the constituency for 14 years and been a councillor since 2017.
Ms Loudon was a primary school teacher for 10 years and has recently been the chairwoman of education resources at South Lanarkshire Council.
Who is Labour’s candidate?
Labour’s candidate Michael Shanks is also a teacher, at a school in Renfrewshire.
He previously made headlines after running along all 6,110 streets in Glasgow.
When can we expect a winner?
South Lanarkshire Council will announce the winner early on Friday.
