Britons will head to the polls today for a snap general election which was called to break the country's Brexit impasse. The ballot is expected to shape how, or whether, the United Kingdom finally quits the European Union almost three and a half years after the EU referendum. Prime Minister Boris Johnson's Conservative Party and Jeremy Corbyn's main opposition Labour Party have presented radically different proposals for ending months of political deadlock over the issue. The electorate, also deeply divided over Brexit, will now have its say in a poll dubbed the "most important" for a generation.

Why is an election being held?

Months of fractious political disagreement over Brexit saw MPs agree in October to hold an early general election. Before that, they had repeatedly rejected the divorce deal brokered by Johnson's predecessor, Theresa May, forcing her resignation. They then moved to block Johnson from pushing his revised Withdrawal Agreement through Parliament at breakneck speed. With no apparent majority among MPs for any course of action over Brexit - resulting in three requests so far to delay the UK's departure - an election appeared to be the natural end-gameastheyear progressed.

How does the vote work?

Voters in 650 constituencies across the UK will elect an MP to the lower chamber House of Commons via the first past the post system. To win, candidates need to get more votes than any of their competitors. A party needs to win 326 seats to secure a majority intheCommonsand be asked to form a government by the monarch, Queen Elizabeth II. Parliament's upper chamber, the House of Lords, is unelected. If no party achieves a majority, there is a hung parliament. In this scenario, the party with the largest vote share may form a minority government, seek

out the support of smaller parties for a "confidence and supply"arrangement, or try to build a formal coalition. On polling day, voting centres will be open from 7:00 -22:00 GMT. Final results from the poll are expected to be declared by the early hours of Friday.

within six months, alongside an option to remain in the EU.The SNP is aligned with Labour in supporting a second referendum, so long as remaining in the EU is an option on the ballot paper, while the Liberal Democrats have pledged to revoke Article 50 and cancel Brexit altogether if they win.

What is expected?

The Conservative Party appears set to win the largest vote share of the vote and possibly a majority of seats. A YouGov study said the Tories were on course for a 28-seat majority in the 650-seat House of Commons under Britain's first-past-the-post system. On November 27, it forecast a 68-seat majority. "The margin of error here could put the final number of Conservative seats from 311 to 367,"YouGov said. The lower end of that range would leave Britain with another hung parliament, where the biggest party does not have a majority, and the very real possibility of Brexit being delayed for years or even cancelled in a second referendum. Among the smaller parties, the pro-European Liberal Democrats are predicted

to win 14 percent of the vote share and 13 seats in Parliament. The Scottish National Party (SNP), which only fields candidates for the 59 constituencies in Scotland, is projected to win 43 seats, but only three percent of all votes cast.

How will the vote shape Brexit?

Johnson has promised to "get Brexit done” by the end of January if his Conservative Party scoops a majority. However, even if Parliament passes the existing withdrawal agreement by that deadline, a potentially gruelling negotiation over the UKand EU's future relationship will begin as the transition period comes into effect. Johnson says this period will not be extended past the end of2020, when it is currently scheduled to end, but there is widespread doubt over whether a trade deal can be concluded before then. The transition period can be extended by up to two years if the UK and EU both agree. If Labour wins, it will ask the EU for another Brexit extension to allow time to renegotiate the current withdrawal agreement. Corbyn wants a softer divorce deal based on a new UK-EU customs union and close EU single market alignment Labour's reworked agreement would be put to a legally-binding second referendum

What else are Britons concerned about?

A sluggish economy, creaking health and social care provision, the unfolding climate crisis, and law and order are among other key concerns. Uncertainty over the UK's future relationship with the EU has seen the economy register its slowest annual rate of growth in almost a decade, with year-on-year growth in the last quarter falling to an anaemic one percent. Meanwhile, the NHS continues to struggle under severe financial pressure, with hospital waiting times now at their worst-ever level on record. A decade of austerity imposed by successive Conservative-led governments has also seen budgets for policing, housing and welfare all dramatically cut.