Prime Minister Boris Johnson on Friday welcomed early election results in Britain's first major vote since Brexit and the pandemic, including a stunning by-election victory for his Conservative party in an opposition Labour stronghold.

The "Super Thursday" local and regional contests could reshape the UK as pro-independence forces in Scotland, where voting for the devolved parliament was also held, bid to break away.

Scotland's First Minister Nicola Sturgeon won re-election in Glasgow and said she was confident her Scottish National Party (SNP) were on track to win a fourth, consecutive election victory.

Johnson has shrugged off questions about costly renovations to his Downing Street flat and campaigned on his record as the leader who finally "got Brexit done Johnson has shrugged off questions about costly renovations to his Downing Street flat and campaigned on his record as the leader who finally "got Brexit done" Photo: AFP / -

"If that's indeed the outcome of this election, I pledge today to get back to work immediately, to lead this country in recovery from Covid, and then, when the time is right, to offer this country the choice of a better future," she said.

The SNP's hopes of securing a majority that Sturgeon says will give her a mandate to demand another referendum received a boost in early counting as her party gained three key seats towards the target.

Opposition Labour party leader Keir Starmer has played down electoral expectations Opposition Labour party leader Keir Starmer has played down electoral expectations Photo: AFP / Tolga Akmen

In early returns in England on Friday, Johnson's Tories were performing strongly, notably winning by a landslide in the northeast parliamentary seat of Hartlepool, in a bitter blow for Labour and its leader Keir Starmer.

The rust-belt town constituency, which is deep in traditional Labour heartlands and had never voted Conservative since its creation in 1974, saw a 16 percent swing to the Tories.

First Minister and leader of the Scottish National Party (SNP), Nicola Sturgeon wants Scotland to break away First Minister and leader of the Scottish National Party (SNP), Nicola Sturgeon wants Scotland to break away Photo: POOL / Jeff J Mitchell

The Tory mayor for Tees Valley, also in northeast England, won re-election, also by a landslide, increasing his share of the vote compared to 2017.

Johnson described the results as "very encouraging".

"What this election shows is that people want a party and a government that is focused on them, focused on delivering change," he added on a whistlestop victory tour of Hartlepool.

A polling station in central Edinburgh closes at 10pm after a day of voting in the first regional elections since Brexit and the coronavirus crisis, after calls in Scotland for a new independence referendum that could reshape the country. A polling station in central Edinburgh closes at 10pm after a day of voting in the first regional elections since Brexit and the coronavirus crisis, after calls in Scotland for a new independence referendum that could reshape the country. Photo: AFPTV / Clara CHARLES

Newly-elected Tory MP Jill Mortimer called her win "truly historic" and accused Labour of taking its people "for granted for too long".

The results continue the trend from the last general election in December 2019, when Brexit was the dominant issue and Conservatives grabbed a string of seats across Labour's so-called "Red Wall" heartlands in northern England.

Opposition Labour party leader Keir Starmer had already played down electoral expectations Opposition Labour party leader Keir Starmer had already played down electoral expectations Photo: AFP / Tolga Akmen

The vote in strongly pro-Brexit Hartlepool, held alongside local elections across much of the country, came about after its Labour incumbent quit over sexual harassment allegations.

In 2019 -- Labour's worst election results since 1935, under the hard-left leadership of Jeremy Corbyn -- around a quarter of Hartlepool's electorate opted for the upstart Brexit Party.

IMAGESElection officials start counting votes in Glasgow the day after the "Super Thursday" regional and local elections. Results in Scotland are due on Saturday, May 8. IMAGESElection officials start counting votes in Glasgow the day after the "Super Thursday" regional and local elections. Results in Scotland are due on Saturday, May 8. Photo: AFPTV / Mathilde BELLENGER

Now, with Britain's withdrawal from the European Union complete and that party rebranded, those voters appeared to flock to the Conservatives.

The result will ratchet up the pressure on Starmer, elected leader a year ago promising to rebuild the party and reconnect with traditional voters.

Senior party MP Steve Reed called the result "shattering". Starmer said he was "bitterly disappointed" and took "full responsibility", pledging to rebuild trust.

In Hartlepool, a giant inflatable Johnson appeared outside the building where the vote count was taking place. The balloon prime minister, complete with trademark scruffy blond hair, gave two thumbs up.

The outcome suggests Johnson remains popular in former Labour strongholds and has benefited from Britain's successful vaccine rollout, despite the country also suffering one of the world's worst Covid-19 death tolls.

Johnson, who has been dogged by scandals in recent weeks, campaigned on his record of finally having "got Brexit done".

He also touted government economic support during the pandemic and the vaccine drive.

Results of voting for local councils in England, regional mayors including in London, and for the devolved assemblies in Wales and Scotland -- expected later Friday and over the weekend -- will give a broader picture of his support.

Tory gains elsewhere across England suggest Starmer faces an increasingly daunting task to unseat Johnson at the next general election due in 2024.

"The structural realignment of party support is clearly going to be the dominant story of the elections in England," said University of Southampton politics professor Will Jennings.

He noted the "feel-good factor" of the vaccine rollout may have helped maintain the recent shifts towards Conservatives.

But Conservative celebrations could be tempered by events in Scotland, where the SNP is eyeing a pro-independence majority to pressure Johnson to allow another referendum on splitting from the UK.

A majority of 55 percent of Scots voted against in 2014.