Britain's rival party leaders dashed around the country on Wednesday in a frantic push for votes in the final hours before a highly-charged snap election aimed at breaking the Brexit impasse.
Polls open at 0700 GMT on Thursday for the third general election in under five years -- and the second since the seismic 2016 referendum vote to leave the European Union.
Parliament's divided parties -- some seeking a swift exit from the EU and others wanting to stay in the bloc -- repeatedly rejected the divorce terms former prime minister Theresa May struck with Brussels.
Johnson, who took office in July, has spent the campaign stressing his "Get Brexit Done" message aimed solely at winning a majority that could let him get his renegotiated deal passed by the end of next month.
Yet a closely-watched poll showed his Conservative Party's lead over the Labour main opposition narrowing.
The YouGov study projected that the Conservatives were on course for a 28-seat majority in the 650-seat House of Commons under Britain's first-past-the-post system.
In an ear;oer poll it had forecast a 68-seat majority.
- Hung parliament? -
"A Conservative majority is the most likely outcome but a hung parliament remains entirely plausible," said University of Kent professor Matthew Goodwin.
A result in which the biggest party does not command a majority raises the possibility of Brexit being delayed for years or even cancelled in a second referendum.
Johnson started the day loading milk bottles onto delivery vehicles in northern England.
He then went baking pies in the country's heartland, touring a Christmas wrapping paper producer in Wales and hammered in a placard in a garden in South Benfleet, east of London.
His message everywhere was the same: literally hammering down the "Get Brexit done" slogan, that he is the man to deliver on the 2016 referendum verdict, with an "oven-ready" deal that can get the divisive process wrapped up.
"The last parliament was so obsessed with arguing about Brexit, they were even arguing about arguing," he said in his polling day message to voters.
"Enough is enough. This election is our chance to end the gridlock but the result is on a knife-edge.
"I want to end the division and bring this country back together again."
He rounded off the tour with a rally at the Copper Box in Stratford, east London: one of the venues built for the 2012 Olympics when Johnson was the city's mayor.
- 'Shock the establishment' -
Turnout will be vital in Britain's first December election in nearly a century. Rain and even snow are forecast for parts of election day, while voters in Britain's most northerly town will have less than six hours of daylight.
Labour leader Jeremy Corbyn is a veteran leftist campaigner who confounded pollsters by coming within a whisker of winning the last election in 2017.
But his vague stance on Brexit and accusations of anti-Semitism in Labour have forced several top members out of the party and cast a shadow over his campaign.
"Boris Johnson won't just keep everything the same; he will make it worse," Corbyn said in his final election rally.
"You can shock the establishment by voting for hope.
"It's time for real change for the many, not the few."
Corbyn's proposal for Brexit is for Labour to strike a more EU-friendly agreement with Brussels. Voters would then choose between that deal and the option of staying in the bloc.
But Brexit remains a political liability for Labour. Corbyn has said as little as possible about the subject and steered attention toward the taxpayer-funded National Health Service.
Labour accuses Johnson of abandoning the principle of free treatment for all by potentially opening up the NHS to "Big Pharma" in a post-Brexit trade deal with US President Donald Trump.
Both Johnson and Trump deny the charge.
- Permanent crisis -
The pollsters suggest Corbyn stands little chance of winning the election outright.
Yet support from the pro-EU Scottish National Party and the Liberal Democrats could still make him the first Labour prime minister since Gordon Brown in 2010.
SNP backing for Labour would come at the cost of Corbyn granting a second referendum on Scottish independence.
The YouGov poll said the SNP was gaining momentum and on course to win 41 seats. But it projected just 15 seats for the anti-Brexit Liberal Democrats.
Some voters voiced dispair at Britain's political mess.
"Everyone thinks it's all going to be over at the end of January if the Conservatives win but it won't," said Judy Wilkinson.
"It will just go on for years."