Boris Johnson is heading for a clear victory in next week’s U.K. general election, according to senior officials in both his ruling Conservatives and the main opposition Labour Party.

Speaking on condition of anonymity, five senior figures drawn from the two biggest parties said Johnson’s campaign promise to “get Brexit done” is winning ground in Labour heartlands in northern England. The officials are familiar with high-level discussions in their parties about the potential outcome.

That looks likely to result in a Tory majority of between 20 and 35 seats in the House of Commons, officials from both parties said. All Conservative candidates have pledged to vote for Johnson’s Brexit deal, meaning even a small majority would in theory ensure the U.K. completes its divorce from the European Union by the Jan. 31 deadline.

Labour Leader Jeremy Corbyn conceded Friday that his personality divides people into those who like him and those who don’t. The Tories have sought to capitalize on that while also trying to minimize the scrutiny Johnson is put under. The prime minister has refused to take his turn in a series of forensic BBC interviews with party leaders, for example.

The final televised debate of the campaign did little to change things, with Johnson sticking to his line of focusing on getting Brexit “done,” while sweeping aside questions of detail. Corbyn in reply argued that Johnson couldn’t be trusted. Each accused the other of racism.

While the prime minister avoided jokes and maintained message discipline, Corbyn was more willing to discuss ideas, at one stage setting out his objections to free-market capitalism.

A YouGov poll afterward found a statistical tie, with 52 per cent saying Johnson had won and 48 per cent giving it to Corbyn, a difference that fell within the margin of error. The Labour leader was viewed as more trustworthy and more in touch with ordinary people, but Johnson was seen as more likable and more prime ministerial.

A summary of recent polls puts the Conservatives on 43 per cent of the vote nationally, and Labour on 33 per cent, a gap that has narrowed over the course of the campaign. Corbyn seemed to have done little to change that in the debate.

But with just under a week to go before the vote, nothing is certain. While Johnson is winning where he needs to, many voters have not made up their minds and others could still switch, campaign officials said.

Johnson triggered the Dec. 12 snap election after months of deadlock over Brexit in parliament, where his Tory party didn’t have a majority. He wanted to force his deal with the European Union into law to ensure the U.K. left the EU by Oct. 31, but lawmakers refused to agree to his fast-track timetable and forced him to request a delay.

National Priorities

The premier has appealed to voters to give him a majority so he can deliver Brexit -- three and a half years after the referendum -- and move on to the country’s other priorities, including investing in the National Health Service and cutting taxes.

It’s a message targeted particularly at voters in the north and center of England, regions which voted to leave the EU in the 2016 referendum but which have traditionally heavily backed the Labour Party.

Many of these so-called “red wall” seats are now moving to support Johnson’s Tories, according to polling, and to the officials in both main parties, who spoke privately about the contest.

While Johnson is on course to triumph next Thursday, small moves in support could make the difference between a result that would deliver a landslide and one which would lead to another hung parliament. That’s because in Britain’s “first past the post” electoral system, the winner takes all in each of 650 electoral districts.

Tim Bale, co-director of the Mile End Institute at Queen Mary University of London, said the polls suggest next week’s election will result in a Tory majority. “At the moment it points to a Tory majority,” Bale said in an interview with Bloomberg Radio on Friday. “Corbyn I think has very little time to close that gap.”