Tory ministers, MPs, advisers and activists will head to Manchester this weekend for their annual conference, probably the last one before the next election.
But the most significant political event of the week will actually be taking place roughly 200 miles north, on the outskirts of Glasgow.
On Thursday, voters in Rutherglen and Hamilton West will choose their next MP in a by-election which will tell us an awful lot about how likely Keir Starmer is to win a Commons majority next year.
It was triggered after the sitting MP, Margaret Ferrier, was effectively sacked by her constituents following her criminal conviction for breaking lockdown rules during the pandemic.
Ferrier won the seat for the SNP at the 2019 general election with a majority over Labour of 5,240.
The circumstances of her departure, alongside the woes which have visited the SNP this year, mean Labour are now the bookies’ favourites to regain a seat they last won at the 2017 election.
However, Starmer’s party need to win well to demonstrate that they really are on the road back to electoral credibility in Scotland.
Senior Labour figures say that winning 20 Scottish seats (up from the one they have at the moment) is a realistic target, while some openly speculate that they could gain more than 30.
Either of those results would, in turn, boost Starmer’s chances of a seismic victory in 2024.
“Given how difficult a position the SNP are in, my sense is Labour have to win quite big in Rutherglen,” polling expert and Tory peer Lord Hayward told HuffPost UK.
“If you’re looking to estimate what’s happening in 12 months’ time, doing well in Scotland will be the difference between Labour having a majority and a clear majority.”
The most recent Scottish opinion poll, by YouGov, showed that support for the SNP has actually gone up again, with Labour dropping back.
That may well explain by Scottish Labour figures are noticeably less bullish about the party’s by-election chances than they were a few weeks ago.
“Our folk are quite confident,” said one Labour veteran. “Our campaign is well organised and our candidate is really good – but the question is what people who have been voting SNP for the past 10 years will do on the day.”
Another Scottish Labour insider said: “I wouldn’t say we’re super confident, but we are cautiously optimistic.
“We’ve spoken to over half the constituency and the feedback is pretty positive. Voters who voted Tory or SNP in the past have left them and we’re working very hard to pull them across.
“But If we don’t win it from here then there is something far wrong.”
One SNP MP who has been canvassing in the seat said there was little hostility for the party on the doorsteps.
“I was expecting an absolute skelping on the doors but it hasn’t been like that at all,” he said.
He added: “A colleague who was predicting a 5,000 Labour majority is now saying it’ll be closer to 3,000, so that gives an indication of the way it’s going.
“It’ll come down to whether we can get out vote out. We might get a lot of SNP supporters staying at home, whereas Labour’s get out the vote operation is usually very good.”
Senior Labour figures compare this by-election to another one which took place in Hamilton in 1967, when Winnie Ewing pulled off a stunning victory to win the seat from odds-on favourites Labour, thereby becoming the SNP’s first MP.
Alex Salmond has described the result as the birth of the modern SNP, and Labour hope a win on Thursday will herald another political dawn north of the border.
To that end, Starmer – who has ordered every member of his shadow cabinet to visit the seat before polling day – was back out campaigning there yesterday.
“Keir sees Scotland as absolutely fundamental,” a senior adviser to the Labour leader told HuffPost UK. “Not just because of the electoral reality, but because he wants to build a narrative that Labour is the party that can unite the country and drive it forward. That’s why he has spent so much time up there.”
The Tory conference will close on Wednesday with Sunak’s make-or-break keynote speech to the party faithful.
However, it will be the verdict of the people of Rutherglen and Hamilton West 24 hours later, rather the prime minister’s warm words, which will tell us more about who will hold the keys to No.10 this time next year.