LONDON (BLOOMBERG) - Across the length of the United Kingdom, politicians are donning hiking boots and fluorescent jackets and arming themselves with torches as they campaign in the cold, wet and darkness ahead of the country's first December election in almost a century.

The shrinking daylight hours mean much of the battle for votes will be conducted at night. The winter also brings the risk of snow and the sort of dramatic flooding that has already hit northern England and become a major issue in the campaign. All of that makes an already unpredictable Dec 12 election more hazardous than any contest in recent years.

"We've got teams of people going out door-knocking every night," said Mr Alex Cole-Hamilton, election campaign director for the Scottish Liberal Democrats. "It's about common sense and putting safety first: look out for black ice, look out for each other in terms of low body temperatures. If your friend is starting to look blue, it's maybe time to head homewards."

There is an open question about how the conditions affect the vote. The British love to complain about the weather and when irritation at discomfort turns into anger at a crisis, it is the government that invariably gets the blame. Prime Minister Boris Johnson's Conservative campaign has already been knocked off course by disastrous flooding that has hit parts of northern England.

FAIR WEATHER VOTERS

After opposition parties attacked the Prime Minister's "woeful" response, Mr Johnson sent in the army to help the relief operation. But on Wednesday (Nov 13), he faced anger from voters.

"What more can we do?" he asked a local woman as he toured the flood-stricken area with reporters and television cameras in tow.

"It's a little bit too late now," she replied.

Then there is the question of how wintry conditions could affect the number of people who turn out to vote on polling day. Turnout could be lower because of bad weather and early sunset times.

Transport could be snarled up, preventing voters from reaching the polls. Some voters may have taken an early winter holiday, while others could be out celebrating at office parties until after polling booths close at 10pm (6am Singapore time).

The timing may slightly benefit Mr Johnson's Conservatives over the opposition Labour Party, according to Mr Philip Cowley, professor of politics at Queen Mary University of London.

TORY BOOST

"In recent elections, Labour have benefited from their mass membership giving them a ground war advantage that should, at least in part, be reduced by the weather," Prof Cowley wrote in a Spectator blog.

"Postal voters also tend to be disproportionately older (and so Conservative), which might also benefit the Tories."

And there is also the question of where students will vote. They are allowed to be registered both where they study and where they live. Most universities break up in the week of the Dec 12 election, making it harder to predict where students will be.

If they are concentrated in university towns, the more left-leaning student population could swing the vote more toward Labour or the Lib Dems in those constituencies than if they are sprinkled around the country at their parents' homes.

There is no conclusive evidence that a winter election affects turnout. In the last December election, in 1923, 71.1 per cent of eligible voters turned out. That compares with 77 per cent in the October vote the following year. The last winter election was in February 1974, when turnout was more than 6 points higher than an October election later that year.

DARK DOORSTEPS

For most campaign teams, the main issues are the cold and the darkness that activists have to cope with when they are walking the streets to make their case to voters, door-to-door. In the Shetland Islands, off the far northern coast of Scotland, for example, there will be fewer than six hours of daylight on election day. Most of Scotland will get fewer than seven hours. And London will get just under eight hours.

When the country went to the polls for the June 2017 election, London enjoyed more than 16 hours of daylight.

Mr Andrew Bowie, the Conservative candidate who is trying to defend his seat of West Aberdeenshire and Kincardine, said the sun will set before 3.30pm in his constituency on Dec 12. He points out that Mr Johnson had tried to secure an election in September, but was thwarted by Parliament.

"Nobody wanted a winter election," said Mr Bowie, clad in a quilted jacket and hiking boots after a drizzly morning of campaigning in Stonehaven, south of Aberdeen. "December is possibly the worst possible time in this part of the world."

HATS AND TORCHES

Mr Cole-Hamilton said his team have been collecting hats and gloves to ensure volunteers are prepared. In another Scottish seat, Conservative candidate Luke Graham said his team has been buying reflective jackets and head torches. He is also concerned about voters being safe at home in the Ochil and South Perthshire seat he is defending.

"People will be opening doors in the dark, and you want to make sure that the people they're being greeted by are bona-fide party workers," Mr Graham said.

In St Albans, a wealthy commuter city north of London, the Liberal Democrat candidate, Ms Daisy Cooper, said her team has adjusted its canvassing strategy.

"Where you're near the city centre, there are more streetlights and people are willing to open their doors," she said. "That's the kind of place you canvass until 8pm."

Further out of town, in villages where older people live, will be off limits. "We won't be knocking on their doors in the dark," Ms Cooper said.

Both Ms Cooper and Mr Bowie said they had been on a big drive to persuade their supporters to register for a postal vote. That is important for ensuring people actually cast their ballots, because they may be deterred from heading out to polling stations on the day itself if there is rain or snow. In 2017, 18 per cent of voters cast their ballots through the mail.

There may be less daylight, but it is not all gloom for the campaign teams.

"We're trying to have fun with it too," said Mr Cole-Hamilton. "We're starting to think about putting Christmas decorations up in our office for when December hits."