Should Boris Johnson persuade enough MPs to vote for a general election on 12 December, it will be the first December election since 1923.
We have become accustomed to parliamentary voting in the spring – all ten elections held since 1979 have been held between April-June.
No elector born after 1960 has ever been asked to vote for an MP outside of these months, saving the odd by-election or so.
But if we consider all 27 general elections since 1918 the picture changes.
Taking the months between October and February when daylight hours reduce, there have been a total of 12 elections.
True, only two are in December, but the fact is that our predecessors would have been used to voting during the cold, damp, dark winter months.
Indeed, in many areas local elections took place in November rather than in May.
What is the effect on voter turnout of holding elections when the chances of poor light and bad weather increase?
We tested this using local council by-elections which take place throughout the year.
More voters turned out during May and June (turnout averaged 37%), but after the clocks went back in October a small but measurable proportion of electors hibernated, with turnout dipping to just 31%.
Interestingly, we repeated this exercise on a new set of elections. The winter decline had disappeared.
The most likely explanation is the much greater use of postal voting.
Many more people, especially those of pensionable age, vote by post. For these folks, it makes no odds whether the sun is shining, or the snow is settling.
If there is an election soon, the parties will be urging their supporters to register for a postal vote.
In 2017, there were 8.2 million registered to vote by post – 18% of the electorate.
Turnout among people who complete a form and put it in the post box was 85% compared with 66% who could only vote at a polling station.
That 19-point gap could prove the difference between winning and losing in a close contest.
Some detractors of a December election are deliberately using the phrase “advent poll”, predicting a clash between nativity plays featuring three wise men and a resolution of the Westminster pantomime.
There are more than 40,000 polling stations used in a UK general election and it is certain that examples of such clashes can and will be found.
But this is no reason to postpone an election despite the disappointment it may cause to school children.
There is a much stronger argument relating to people voting in person.
A recent Sky Data poll found that 12% of all respondents believed crime to be the most important issue facing the country.
Across London, where Labour is defending 49 of 73 parliamentary seats, that figure rises to 17%.
Labour will argue that a winter election might jeopardise its chances in some parts of the capital, especially if younger people not registered for a postal vote are deterred from voting.
Another objection will be raised by the Association of Electoral Adminstrators.
They argue that many aspects of electoral administration are already under strain.
For example, Sky News found that more than half a million EU citizens might have lost their vote in this year’s European elections.
A snap winter poll will bring new pressures on an already creaking system.
In other ways a winter election is no longer the impediment it might have been.
The polling industry no longer stops people in the street for their views on issues and party choice.
Few, if any, politicians stand on the town hall balcony and impress eager electors with their finely-honed rhetoric.
Ask yourself: “Do I know anyone who has attended a hustings, whatever that is?”
While it is true that party canvassing efforts might be limited by the fact that many people don’t answer the door after dark, this style of campaigning is becoming old-fashioned.
It’s digital not analogue.
Labour impressed with its social media campaign in 2017 but there are signs the Conservatives are investing heavily in this area.
The one party that might be adversely affected when investment in online advertising is king is the Liberal Democrats, whose pavement politics is more suited to local campaigns.
Of course, MR Johnson may not get his way this time and a December date is ditched because Labour sees no advantage to an election now, unlike June 2017.
But the prime minister’s response to no election will be to repeatedly take his opposite number and his party to task.
If that effort succeeds and Labour starts to slide in the polls, then there comes a point when the party feels compelled to fight a general election.
A December election
The general election held on 6 December 1923 was called by the new Conservative prime minister, Stanley Baldwin, who assumed office after the incumbent, Andrew Bonar Law, became ill.
Mr Baldwin did not need to call an election since his party had won a majority of 74 seats only a year before.
But he sensed an opportunity to strengthen his grip.
His plan backfired, the Conservatives lost seats and a hung parliament followed.
The emerging Labour Party, led by Ramsay McDonald, formed a minority government but this lost a vote a confidence and a third general election followed in October 1924.
Then, Mr Baldwin won with a landslide 210 majority, Labour finished second and the Liberals were virtually obliterated.
Feel free to draw your own parallels with these events.
Should Boris Johnson persuade enough MPs to vote for a general election on 12 December, it will be the first December election since 1923. We have become accustomed to parliamentary voting in the spring – all ten elections held since 1979 have been held between April-June.