An old rule of politics is that British governments tend to lose midterm by-elections. That makes the resounding defeat of Labour in the centre-left stronghold of Hartlepool by a Conservative party in power for 11 years all the more extraordinary. Extrapolating too much from a town that is the 10th most economically deprived and one of the most pro-Brexit in England is unwise. Yet coupled with early signs that Labour lost ground to the Tories in council votes, too, Thursday’s elections in England have provided a boost to the government — and left the opposition facing searching questions.

What is clear is that Boris Johnson’s government has emerged largely unscathed by its botched handling of much of its Covid-19 response. The well-oiled vaccine rollout and stirrings of economic reawakening have largely erased memories of the misjudgments that have left the UK with more than 127,000 deaths. Despite accusations of cronyism and question marks over his integrity, moreover, the Old Etonian prime minister still seems able to charm wide and often unexpected areas of England — if not Scotland, where a pro-independence majority may yet strain the ties of the UK.

Confounding Labour’s urgings that it is time for a change after a decade of Toryism, many voters perceive this as a new government. Johnson has not just dissociated himself from the Cameron and May administrations but the Thatcherite past. The self-described “Brexity Hezza” — referring to Michael Heseltine, Margaret Thatcher’s more economically interventionist rival — has shifted Tory politics away from its former devotion to the free market.

Particularly in formerly Labour-supporting “Red Wall” seats such as Hartlepool, voters are disillusioned with both Labour and Tory politics of recent decades. They have backed the Johnson Conservatives and their pledge to “level up” left-behind regions as seeming to offer a break with the past.

For the government, this is double-edged. The more it wins such seats, the more pressure it is under to set out its levelling-up strategy, and deliver. That pressure will intensify as coronavirus and the “vaccine bounce” recede. Throwing some money at local improvement projects has bought time. But it will not fix the structural problems — of skills, productivity and creaking infrastructure — that “new” Tory voters are looking to it to address.

Hoping the Tories fail, however, does not amount to a strategy for Labour. Replacing the unreconstructed socialist Jeremy Corbyn with the more polished Sir Keir Starmer has proved insufficient to win back Brexit-voting post-industrial towns. This week’s setbacks will reopen the struggle with the Corbynite left for the party’s soul. The fact Labour is set to continue in power in Wales after 22 years shows some of its old strongholds remain — and suggests the pandemic may have rewarded incumbents beyond the Tory government at Westminster. But these, plus Labour’s “new” heartlands in some of England’s big cities, are far from enough to put it back on a path to power.

In truth, areas such as Hartlepool have been trending away from Labour for decades as the traditional industrial working class has aged and shrunk. Labour’s sister parties in continental Europe are suffering from similar demographic shifts; hopes for the centre-left in Germany lie with the Greens more than the Social Democrats. Some of them, too, are struggling against opponents that have combined rightwing populism with promises of more spending. It is this formula that Johnson’s Conservatives have now partially co-opted, so far with success.