London CNN  — 

The tectonic plates of British politics have shifted after Britons resoundingly voted to put an end to 14 years of Conservative rule, and deliver a landslide victory for the Labour Party.

Labour’s victory is bigger than the party could have imagined until fairly recently. At the last general election in 2019, it slumped to its worst defeat in more than 80 years and appeared set for a long period in the political wilderness.

But the party has since rebuilt itself under the leadership of Keir Starmer, who will now become the next prime minister of the United Kingdom.

Under Britain’s first-past-the-post voting system, people in 650 constituencies across the nations of England, Scotland, Wales and Northern Ireland have voted to select their member of parliament (MP) to represent the area. Votes were counted overnight and the final ones will be tallied through Friday.

A party needs 326 seats to officially win, a milestone that Labour cleared at around 5 a.m. local time on Friday, and the new government will have a commanding majority in the next parliament.

Because of its electoral system, Britain can see large discrepancies between the share of seats won by a party and its share of the popular vote.

If support for one party – or antipathy towards another – is spread fairly evenly across the country, it does not need to win a large share of the popular vote to win a huge majority of seats in parliament.

The results represent one of the largest swings in British political history, and a stunning defeat for the Conservative Party after 14 years in government, bringing a brutal end to Rishi Sunak’s premiership.

Britain’s traditional third party, the Liberal Democrats, also enjoyed a huge bump, going from just 11 seats won at the 2019 general election to more than 60.

Nigel Farage’s right-wing, populist Reform UK party won its first seats and came second in many more, splitting the right-wing vote and contributing to the Conservatives’ losses.

Meanwhile, in Scotland, the Scottish National Party (SNP) has lost multiple MPs, with its number of seats possibly dipping to single digits from 48 in 2019.