LEFT: Britain's Prime Minister Boris Johnson speaks to lawmakers during the election debate in the House of Commons, London, Monday Oct. 28, 2019. 
RIGHT: Britain's main opposition Labour Party leader Jeremy Corbyn speaks to lawmakers during an election debate in the House of Commons, London, Monday Oct. 28, 2019.
PHOTO: House of Commons via AP
LEFT: Britain's Prime Minister Boris Johnson speaks to lawmakers during the election debate in the House of Commons, London, Monday Oct. 28, 2019. RIGHT: Britain's main opposition Labour Party leader Jeremy Corbyn speaks to lawmakers during an election debate in the House of Commons, London, Monday Oct. 28, 2019.
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(CNN) —  

It’s beginning to look a lot like campaigning season (everywhere you go).

British voters are heading to the polls for the fourth time in less than five years, after lawmakers backed Prime Minister Boris Johnson’s gamble to break the country’s crippling political deadlock and hold an election two weeks before Christmas.

The country’s weary voters will be forced to endure an onslaught of photo calls, a daily slew of opinion polls and a fresh flood of campaign leaflets pouring through their letterboxes.

But this year, the well-worn politician’s cliche is true: this vote really is unique.

Britain hasn’t held an election in December since 1923. It hasn’t witnessed such paralysis in Westminster a generation. And while the prospect of trudging to a polling station on a chilly evening a fortnight before Christmas may fill some with dread, the vote will take the temperature of a nation whose position in the world is in flux, and whose future is far from certain.

So, as we begin six weeks of heated winter campaigning, here’s a guide to everything you need to know.

Why is an election happening now?

The real question is why has it taken so long. Since former Prime Minister Theresa May’s disastrous gamble on a snap election in 2017 deprived her of a working majority in the House of Commons, Britain has been in a political standstill. That result prevented May from passing her Brexit deal three times and dealt Johnson a series of defeats over his own Brexit strategy.

Thanks to a piece of relatively recent legislation, the Fixed-Term Parliaments Act, the next election was not due to take place until 2022. But Johnson came to the same conclusion as May, that the only way out of the impasse was to hold an early vote in an attempt to seek a parliamentary majority to enact his Brexit plan.

Opposition MPs finally backed his call on Tuesday, on the fourth time of asking, after Britain’s third Brexit extension gave the country time to sort out its future.

Jeremy Corbyn campaigns during the 2017 general election.
PHOTO: Leon Neal/Getty Images
Jeremy Corbyn campaigns during the 2017 general election.

How will it work?

In the UK, voters don’t elect a prime minister directly. Instead, they elect a Member of Parliament (MP) to represent their local constituency. The leader of the party which wins a majority of the UK’s 650 constituencies automatically becomes Prime Minister.

That means a party needs to win 326 seats to form a majority government. If no group meets that number, the party with the most seats can seek the support of smaller parties, either to join in an official coalition, as the Liberal Democrats did for the Conservatives between 2010 and 2015, or support them on a more informal basis, as the Democratic Unionist Party has done since 2017.

Who’s going to win?

Johnson clearly likes his chances enough to have called a vote. He’s enjoying a comfortable lead in the opinion polls of anything between 3 and 15 per cent, depending on which pollster you believe.

But May was sitting even prettier when she called the 2017 vote, before a surprisingly strong performance from Labour’s Jeremy Corbyn upended the predictions and forced a close result. Corbyn is historically a good campaigner, and if the numbers are tight again, his party has the benefit of having more potential coalition partners than the Conservatives.

And that wild disparity in the polls tells you something else – that the electorate is incredibly volatile at the moment. Pollsters agree that traditional party loyalties are fracturing, and that voters are defining themselves more along how they feel about Brexit. That makes the result very hard to predict – and could result in some unexpected local fluctuations.

It’s a safe bet to say that the largest party will either be the Conservatives or Labour. No other party is in with a chance over overtaking them. But it’s entirely possible that neither will win an overall majority. The Liberal Democrats will hope to capitalize on the clarity of their anti-Brexit position and substantially increase their tally of 20 MPs. On the other end of the spectrum, Nigel Farage’s Brexit Party hopes to take advantage of the Conservatives’ failure to take the UK out of the EU by October 31 and gain its first representation in Parliament.

In Scotland, the Scottish National Party, which has 35 MPs, hopes to regain some of the seats it lost to a resurgent Conservative Party last time around. (The Conservatives’ popular leader in Scotland, Ruth Davidson, is standing down.

Who can vote?

British citizens over the age of 18, plus qualifying Irish and Commonwealth citizens living in the UK, are able to vote – as long as they’re registered before the deadline, which will come a few weeks before polling day.

16- and 17-year-olds and EU nationals can’t take part, despite a last-minute push from some opposition parties to Tuesday to include them in the franchise for this election.

You can check whether you’re eligible and register to vote here.

What are the issues?

Brexit has turned into a tussle for the soul of the country, so it’s no surprise to learn that it will take center stage throughout the campaign. The main parties all have drastically different proposals on the matter; the Conservatives will tout Boris Johnson’s deal with the EU and claim they can get Brexit “done,” while Labour will negotiate a softer Brexit before giving the public the final say in a second referendum.

The Liberal Democrats, meanwhile, want to scrap Brexit altogether, and the Brexit Party are pursuing a no-deal split.

But close watchers of British politics will recall that the 2017 poll was supposed to be all about Brexit too – in reality, voters care about other issues as well.

Boris Johnson during the 2016 EU referendum campaign.
PHOTO: Christopher Furlong/Getty Images
Boris Johnson during the 2016 EU referendum campaign.

As per tradition, the Labour Party will likely make the revered National Health Service a central tenet of its campaign – and in particular the issue of whether a post-Brexit trade deal with the US will open up the health service to American commercialization.

Labour leader Jeremy Corbyn, who has pushed the Labour Party further to the left, is also expected to unveil a dramatic swath of policy proposals; last time around, he touted the abolition of tuition fees, the nationalisation of Britain’s railways, water and energy companies, and an increased tax on Britain’s highest earners.

The Conservatives, meanwhile, also look set to highlight a commitment to the health service, touting increased investment in hospitals. They are also likely to pitch themselves as the party of law and order as concern over crime on British streets rises. The economy, so closely tied to the country’s Brexit fate, will be debated at length too, while issues such as social care, migration and education always rank highly amongst the priorities of British voters.

Will this vote break the Brexit deadlock?

In Britain’s fractured political climate, little is certain.

The rise of smaller parties means the possibility of a hung parliament is greater now than in previous decades. If the 2019 election goes the same way as those in 2010 and 2017, and fails to deliver a party with an overall majority, Brexit could go in a number of different directions.

A hung parliament with a minority Conservative government would likely mean more of the same paralysis that has dogged British politics for the past year. Johnson would likely be forced to try again to get his Brexit deal through Parliament, with no guarantee of success.

If Labour emerges as the largest party, that makes a second Brexit referendum more likely, given that’s also the ambition of the Liberal Democrats and the Scottish National Party.

And even if the Conservatives won a majority on the back of their promise to “get Brexit done,” the saga won’t be over. Johnson would be able to get his deal through Parliament by the next deadline – January 31 – but that’s only the start. Months of negotiations with the EU would follow about a future trading partnership, and the risk of a no-deal Brexit could return all over again if a trade deal isn’t concluded by the end of the Brexit transition period in 2020.

So while this vote will likely set a new Brexit course for Britain, it would be naive to think the issue will be off the agenda by the new year. Sorry.

Why is this all happening in December?

British votes wanted nothing more for Christmas than to be forced to trudge through the winter gloom to church halls, community centers and elementary schools in order to mark an “X” on a piece of paper with a stubby pencil. (British elections are notoriously low-tech.)

And lo, they got their wish!

This will be the country’s first December election since 1923, but the urgency of the new January 31 Brexit deadline and the extent of the parliamentary deadlock has forced the poll.

A polling station during the UK's last December election in 1923.
PHOTO: Topical Press Agency/Hulton Archive/Getty Images
A polling station during the UK's last December election in 1923.

Still, a pre-Christmas vote will present a number of unique challenges. Sunset will come before 4 p.m. across Britain on polling day, and it’s almost certain to be cold, which could have an impact on turnout.

Parties also face the challenge of getting voters excited about their agendas at a time when most people have their mind on other things, and when long nights threaten dampen Brits’ revolutionary fervor.

Are people calling it ‘Brexmas’ yet?

Regrettably, yes, it seems like this is becoming a thing.