UK voters go to the polls for an incredibly uncertain election which will decide the fate of Brexit

• British voters go to the polls on Thursday for an incredibly uncertain general election.
• The result will shape the country's future for decades and could send political shockwaves around the world.
• A victory for Prime Minister Boris Johnson would mean Britain will soon leave the EU before radically changing its political and economic settlement as it breaks away from European trade laws.
• A victory for opposition leader Jeremy Corbyn would trigger a radical new political agenda of higher public spending and taxation.
• Opinion polls suggest either a hung parliament led by Corbyn or a landslide Conservative victory under Johnson are possible.
• Visit Business Insider's homepage for more stories.

Voters go to the polls in the United Kingdom on Thursday for the most important general election in decades.

The vote was triggered by Prime Minister Boris Johnson in order to secure a large enough parliamentary majority to push through Brexit after three years of deadlock.

Opinion polls suggest the result is incredibly uncertain, with both a landslide majority for Johnson's Conservative Party or another hung parliament, highly feasible outcomes.

A Johnson victory would mean that Britain would likely leave the EU at the end of January 2020, before immediately entering an 11-month transition period during which Johnson would seek to negotiate a new trade deal with the EU.

However, if Johnson falls short, then the parliamentary mathematics means that opposition Labour party leader Jeremy Corbyn would be favourite to become prime minister of a new coalition government.

If that happens then the UK would head rapidly for a second referendum on Brexit and a radical left-wing domestic programme which could completely change the economic settlement in the UK.

Either way, the result on Friday is set to be a dramatic one, the impact of which will be felt around the world.

Too close to call?

The UK polling industry has had a shaky record in recent elections, with most pollsters calling the outcome of the last three general elections largely wrong.

The polls in this year's contest are particularly variable with some pollsters forecasting a landslide Johnson win while others suggest the UK is heading for yet another hung parliament.

Where all the pollsters agree is that Johnson's Conservatives will be the largest party. However, merely being the largest party won't necessarily be enough for Johnson to cling onto Downing Street.

With little to no allies among opposition parties, Johnson would likely lose his party's grip on power if he fails to win an outright majority. Corbyn's Labour party, on the other hand, would be favourites to form a government, possibly with the support of the Scottish National Party or the Liberal Democrats.

However, the margins are very fine and it is possible that there will be no viable coalition for either a Conservative or Labour government. If that is the case then Britain is heading for yet more political uncertainty and a probable further general election in the new year.

The Brexit election?

Johnson has sought, with some success, to frame this election as being about Brexit. This has enabled him to forge a coalition of support which contains both former supporters of Nigel Farage's Brexit Party as well as many former Labour voters, who voted to leave the European Union in the 2016 referendum.

This strategy has led to many formerly safe Labour seats in parts of Northern England, to become targets for Johnson's party.

However, the flipside of this strategy is that some southern seats, which were formerly safely held by Johnson's party are now up for grabs by other pro-European parties. That has led to several high-profile members of Johnson's government, including Johnson himself, at risk of losing their seats.

Johnson's strategy has also come somewhat unstuck in the final weeks of the campaign as opposition parties have been successful in framing the campaign on other issues.

An end to austerity?

A decade of public sector cuts, initiated by David Camerons' Conservative-led government in 2010 has led to many public services in the UK struggling to cope. Under particular strain is the publicly-funded National Health Service, which recent statistics suggest is failing to cope with rising demand for its services.

The funding and staffing crisis in the NHS has dominated the latter stages of this campaign with a picture of a four-year-old boy forced to lay on the floor while waiting for emergency care, becoming a focal point of the final days of campaigning.

A viral clip of Johnson refusing to look at a picture of the boy, before snatching a reporter's phone away as he was trying to show the prime minister the photo, became a huge moment in the campaign and symbolised what Johnson's opponents claim is his inability to empathise with the general public.

Both the opposition Labour party and Johnson himself have sought to capitalise on public concern over healthcare in the UK, with Johnson promising new funding and Labour's Jeremy Corbyn warning that Johnson will "sell-off" the NHS as part of a post-Brexit trade deal with the NHS.

Leaked documents, released by Corbyn, detailing talks about drug pricing between the UK and US governments, also became a major focal point in the campaign.

A battle between two political radicals

If Corbyn defies the polls and emerges as the winner of today's election, then he plans to radically change the direction of the UK. His party's manifesto promises a massive programme of nationalisation of key industries as well as huge increases in public spending.

His proposals, including free broadband for all UK citizens, have been met positively by many voters according to the polls while being ridiculed by others.

However, despite significant uncertainty over the result, the most likely outcome still remains that Boris Johnson will be successful in gaining the parliamentary majority he seeks.

If he is successful then it will mean that Britain is heading for a radically different economic and political settlement outside of the frame of the European Union.

Johnson's commitment to diverge from trade and customs regulations with the EU will put the future of many UK businesses, which rely on close trading ties with Europe, at risk. Similarly, Johnson's plan to forge a closer relationship with the US will inevitably mean that Britain has to alter its long-held food and trading standards in ways that will prove deeply controversial.

Johnson is a mercurial political figure who has a record of being socially liberal while Mayor of London but economically Conservative since re-entering parliament and becoming the leader of his party. His party's manifesto is short on detail leaving opponents fearful that he will seek to dramatically change the shape of Britain's political landscape if he is victorious on Friday.

Whatever happens, British voters have a momentous decision in their hands as they head to the polls on Thursday.

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