Two weeks before an election that is expected to catapult him into 10 Downing Street, the leader of Britain’s Labour Party, Keir Starmer, is tiptoeing on the campaign trail, the latest practitioner of the “Ming vase strategy.”
The phrase, which refers to a politician gingerly avoiding slips to protect a lead in the polls, is credited to Roy Jenkins, a more freewheeling British politician, who likened a previous Labour candidate, Tony Blair, on the eve of his 1997 landslide, to a man “carrying a priceless Ming vase across a highly polished floor.”
In truth, Mr. Starmer has been carrying the vase for a lot longer than this six-week campaign. He has nursed his party’s double-digit polling lead for more than 18 months, methodically repositioning Labour as a credible center-left alternative to the divided, erratic, sometimes extremist Conservatives.
It’s the culmination of an extraordinary four-year project, in which Mr. Starmer, 61, purged his left-wing predecessor, Jeremy Corbyn, and his loyalists; went after the anti-Semitism that had contaminated the party’s ranks; and pulled its economic and national security policies closer to the center.
“When he first became leader in 2020, he made it his business to take away all the negatives that prevented people from voting Labour in 2019,” said Steven Fielding, an emeritus professor of political history at the University of Nottingham. As a result, “He’s been able to expand the pool of voters.”
Robert Ford, a professor of political science at the University of Manchester, said, “Four years ago, Keir Starmer was basically offering Corbynism with a human face — and he’s ditched all that. He’s moved to the center because the incentives have moved there, and the audience has moved there.”
It is tempting to compare Mr. Starmer’s remaking of the Labour Party to that of Mr. Blair in the 1990s. Both took their party out of the political wilderness by rebranding it as business-friendly, more about economic opportunity than tax-and-spend liberalism or socialist-style wealth redistribution.
Mr. Blair’s New Labour loosened the links between the party and trade unions, much as Mr. Starmer cast off Mr. Corbyn’s pledge to renationalize Britain’s energy network (though Labour does plan to create a new publicly owned company, Great British Energy, to stimulate investment in clean energy).
Still, analysts say there are profound differences between the New Labour of 1997 and the Labour Party of today. Mr. Blair campaigned as an apostle of the global economy, one who believed that government should not intervene in markets. Mr. Starmer takes a far more activist approach, arguing that a robust state role is critical to providing economic security for working-class people.
Security is a mantra that runs through Labour’s messaging, from the economy to immigration and national security. That reflects Mr. Starmer’s view of a world that has become economically more turbulent since the financial crisis of 2009 and geopolitically more dangerous since Russia’s invasion of Ukraine.
“The very foundation of any good government is economic security, border security, national security,” Mr. Starmer said in his first major campaign speech last month in the coastal town of Lancing. “This is the foundation, the bedrock that our manifesto and our first steps, will be built upon.”
The contrast between Mr. Starmer and Mr. Blair, Professor Fielding said, is similar to that between former President Bill Clinton, who preached the virtues of free trade and the global economy, and President Biden, who has avoided trade deals in favor of vast new investments in America’s infrastructure.
“Blair really was a globalizing liberal: free trade, economic growth, dynamism is good, disruption is good,” Professor Ford said. “Starmer’s worldview is very different: he thinks change needs to be managed and controlled.”
Mr. Starmer, like Mr. Biden, will inherit an economy that is still shaking off the effects of the Covid pandemic. Britain’s growth has trailed that of the United States, and its public services, notably its revered National Health Service, are depleted after years of fiscal austerity under Conservative-led governments.
A Labour government will operate under strict financial constraints, which has raised questions about whether Mr. Starmer will have to raise taxes to pay for promised investments in the N.H.S. and other public services. He has issued a blanket promise not to raise taxes on “working people.”
But Labour is expected to raise taxes on oil and gas companies, private equity firms and high-income foreigners who live in Britain. It will also remove a tax break for private schools, a move that it says will pay for an additional 6,500 public school teachers.
Labour’s promise to be fiscally prudent is personified by Rachel Reeves, who would be the chancellor of the Exchequer in the new government. A onetime banker and economist at the Bank of England, Ms. Reeves confirmed last February that the party would scale back its ambitious climate policy, projected to cost 28 billion pounds ($35 billion) a year, until Britain’s finances stabilized.
That reversal was calculated to shield Labour from accusations that it would run a tax-and-spend government, though Prime Minister Rishi Sunak still accuses it of planning to raise taxes on households — a claim that Labour disputes.
Ms. Reeves is part of an inner circle around Mr. Starmer that reflects his moderate instincts. Some of them refused to serve under Mr. Corbyn, though as Mr. Starmer’s opponents note, he was on his predecessor’s team.
“These people are signaling to more centrist voters that this is a Labour Party you can feel relatively comfortable with,” said Jill Rutter, a senior research fellow at the U.K. in a Changing Europe, a research group.
Mr. Starmer has also shown no interest in relitigating the bitter debate over Brexit. He has ruled out returning to the European Union, though he has opened the door to a closer trade relationship with Brussels. The Conservatives used that issue to their advantage in 2019 by promising to “get Brexit done.”
On foreign policy, too, Mr. Starmer has worked to inoculate Labour from the accusations of a lack of patriotism that haunted it under Mr. Corbyn, who once said he hoped to see the NATO alliance disbanded. Mr. Starmer has vowed to increase spending on the military and maintain Britain’s steadfast support of Ukraine.
He has also hewed closely to the Conservative government’s support of Israel in the war in Gaza. That is in keeping with his campaign to rid Labour of anti-Semitism, though it has alienated some Muslim supporters, and looms as one of the party’s only stumbling blocks in the July 4 election.
“It’s the one part of their tent that has sprung a leak,” Professor Ford said.
Of all the reasons Labour appears more electable, analysts said, the biggest might simply be the collapse of its opponents, not just the Conservatives but also the Scottish National Party, which has been discredited by a financial scandal involving its former leaders. Few analysts would have predicted, in the wake of Labour’s landslide defeat in 2019, that it would be on the cusp of national power today.
“Keir Starmer has been incredibly lucky,” Ms. Rutter said. “He’s managed to rehabilitate the Labour Party at the same moment that his opponents have downgraded their offer to voters significantly.”
