Britain’s Labour Party swept to power Friday after more than a decade in opposition, official results showed, as a jaded electorate appeared to hand the party a landslide victory but also a mammoth task of reinvigorating a stagnant economy and dispirited nation.

Labour leader Keir Starmer will officially become prime minister later in the day, leading his party back to government less than five years after it suffered its worst defeat in almost a century. In the brutal choreography of British politics, he will take charge in 10 Downing St. hours after the votes are counted – as Conservative leader Rishi Sunak is hustled out.

“A mandate like this comes with a great responsibility,” Starmer acknowledged in a speech to supporters, saying that the fight to regain people’s trust “is the battle that defines our age.”

Speaking as drawn broke in London, he said Labour would offer “the sunlight of hope, pale at first but getting stronger though the day.”

Sunak conceded defeat, saying the voters had delivered a “sobering verdict.”

Labour’s triumph and challenges

For Starmer, it’s a massive triumph that will bring huge challenges, as he faces a jaded electorate impatient for change against a gloomy backdrop of economic malaise, mounting distrust in institutions and a fraying social fabric.

“Nothing has gone well in the last 14 years,” said London voter James Erskine, who was optimistic for change in the hours before polls closed. “I just see this as the potential for a seismic shift, and that’s what I’m hoping for.”

Anand Menon, professor of European Politics and Foreign Affairs at King’s College London, said British voters were about to see a marked change in political atmosphere from the tumultuous “politics as pantomime” of the last few years.

“I think we’re going to have to get used again to relatively stable government, with ministers staying in power for quite a long time, and with government being able to think beyond the very short term to medium-term objectives,” he said.

Britain has experienced a run of turbulent years — some of it of the Conservatives’ own making and some of it not — that has left many voters pessimistic about their country’s future. The U.K.’s exit from the European Union followed by the COVID-19 pandemic and Russia’s invasion of Ukraine battered the economy, while lockdown-breaching parties held by then-Prime Minister Boris Johnson and his staff caused widespread anger.

Johnson’s successor, Liz Truss, rocked the economy further with a package of drastic tax cuts and lasted just 49 days in office. Rising poverty and cuts to state services have led to gripes about “Broken Britain.”

While the result appears to buck recent rightward electoral shifts in Europe, including in France and Italy, many of those same populist undercurrents flow in Britain. Reform UK leader Nigel Farage has roiled the race with his party’s anti-immigrant “take our country back” sentiment and undercut support for the Conservatives, who already faced dismal prospects.

The exit poll suggested Labour was on course to win about 410 seats in the 650-seat House of Commons and the Conservatives 131.

With a majority of results in, the broad picture of a Labour landslide was borne out, though estimates of the final tally varied. The BBC projected that Labour would end up with 410 seats and the Conservatives with 144.

Conservative vote collapses as smaller parties surge

Even that higher tally for the Tories would leave the party with the fewest seats in its nearly two-century history and cause disarray.

The result is a catastrophe for the Conservatives as voters punished them for 14 years of presiding over austerity, Brexit, a pandemic, political scandals and internecine Tory conflict. The historic defeat leaves the party depleted and in disarray and will likely spark an immediate contest to replace Sunak as leader.

In a sign of the volatile public mood and anger at the system, some smaller parties picked up millions of votes, including the centrist Liberal Democrats and Farage’s Reform UK. Farage won his race in the seaside town of Clacton-on-Sea, securing a seat in Parliament on his eighth attempt, and Reform has won four seats so far.

The Liberal Democrats won many more than that on a slightly lower share of the vote because its votes were more efficiently distributed. In Britain’s first-past-the-post system, the candidate with the most votes in each constituency wins.

Labour was cautious but reliable

Hundreds of seats changed hands in tight contests in which traditional party loyalties come second to more immediate concerns about the economy, crumbling infrastructure and the National Health Service.

Labour did not set pulses racing with its pledges to get the sluggish economy growing, invest in infrastructure and make Britain a “clean energy superpower.”

But the party’s cautious, safety-first campaign delivered the desired result. The party won the support of large chunks of the business community and endorsements from traditionally conservative newspapers, including the Rupert Murdoch-owned Sun tabloid, which praised Starmer for “dragging his party back to the center ground of British politics.”

Conservative missteps

The Conservative campaign, meanwhile, was plagued by gaffes. The campaign got off to an inauspicious start when rain drenched Sunak as he made the announcement outside 10 Downing St. Then, Sunak went home early from commemorations in France marking the 80th anniversary of the D-Day invasion.

Several Conservatives close to Sunak are being investigated over suspicions they used inside information to place bets on the date of the election before it was announced.

Sunak has struggled to shake off the taint of political chaos and mismanagement that’s gathered around the Conservatives.

In Henley-on-Thames, about 40 miles (65 kilometers) west of London, voters like Patricia Mulcahy, who is retired, sensed the nation was looking for something different. The community, which normally votes Conservative, may change its stripes this time.

“The younger generation are far more interested in change,’’ Mulcahy said. “But whoever gets in, they’ve got a heck of a job ahead of them. It’s not going to be easy.”