Liz Truss ahead in polls amid hopes ballot delay could benefit Rishi Sunak

Sixty per cent of Conservative Party members polled by YouGov say they intend to vote for Truss

Liz Truss and Rishi Sunak in the BBC Conservative Party leadership debate in Stoke-on-Trent, England, on July 25. AP

A new poll shows Rishi Sunak has lost ground in the Tory leadership race but a ballot delivery delay over security concerns could give him more time to make an impression before votes are cast.

Foreign Secretary Liz Truss is well ahead of the former chancellor in a YouGov poll, with her lead increasing to 34 points.

The research was conducted between July 29 and August 2, and shows 60 per cent of party members polled say they intend to vote for Ms Truss, up from 49 per cent since July 20 to 21 when the two first made the final cut.

Support for Mr Sunak has dropped from 31 per cent to 26 per cent according to YouGov, while the rest of the 1,043 Conservative party members polled say they are undecided or will not vote.

In a further blow to him, YouGov data also showed 83 per cent of those who say they intend to vote for Ms Truss also say they have made up their minds.

Only 17 per cent say they might still change their mind while 29 per cent of Mr Sunak’s supporters say they might still vote differently.

UK Conservatives on the leadership campaign trail - in pictures

Candidates Rishi Sunak and Liz Truss at the Conservative Party leadership election hustings at Wembley Arena, London. This was the final hustings attended by Tory Party members who will vote for the new leader and next prime minister. EPA

Liz Truss addresses Conservative Party members at Wembley Arena. AP

Mr Sunak puts forward his case to be leader while speaking at Wembley Arena. Bloomberg

Mr Sunak visits his family's old business, Bassett Pharmacy in Southampton, while on the campaign trail. Reuters

Ms Truss speaks to staff at Condimentum Ltd at the Food Enterprise Park in Norwich. Getty Images

A Rishi Sunak supporter at a hustings event in Norfolk. PA

Mr Sunak greets people at a leadership hustings in Manchester. Bloomberg

Ms Truss poses for a selfie with a supporter as she arrives for the event in Manchester. Getty

Rishi Sunak looks through the sights of an anti-tank missile launcher, supplied to Ukraine, during a visit to the Thales Defence System plant in Belfast, Northern Ireland. AP

Liz Truss at a Conservative Party leadership campaign event in Belfast. Getty

Liz Truss meets supporters before a hustings in Perth, Scotland. Getty

Rishi Sunak speaks during a campaign visit to Cluny Castle in Inverurie, Scotland. Getty

Police hold back protesters outside Perth Concert Hall, Scotland, where Conservative leadership candidates Liz Truss and Rishi Sunak were speaking. PA

A mural showing the two leadership contestants appears on a wall in Belfast, Northern Ireland. AP

Rishi Sunak during a visit to St John's Wood Synagogue, north London. PA

Liz Truss at the Conservative Party leadership election hustings in Cheltenham. EPA

Rishi Sunak during a hustings event in Cheltenham. Reuters

Liz Truss speaks to scientists during a campaign visit to a life sciences laboratory at Alderley Park in Manchester. PA

Rishi Sunak during a campaign hustings in Darlington, England. Bloomberg

Liz Truss meets party members before she speaks at the Darlington campaign hustings. Getty

Rishi Sunak arrives for the Darlington hustings. Getty

Liz Truss plays pool during a visit to the Onside Future Youth Zone in London. Reuters

Rishi Sunak looks at a book with Teddy Openshaw, 4, as his father, Henry, looks on after a Conservative leadership campaign event in Ribble Valley, Lancashire, England. Getty

Liz Truss plays table tennis with former Conservative party leader Iain Duncan Smith during a visit to the Onside Future Youth Zone in London. Reuters

Liz Truss with supporters at a campaign event in Solihull, England. Reuters

Rishi Sunak attends a campaign event held by his party in Bexhill, England. Reuters

A protester is removed as Ms Truss speaks during the Conservative Party leadership hustings in Eastbourne. Bloomberg

Mr Sunak speaks at an event in Edinburgh. PA

Ms Truss leaves the hall in Exeter, south-west England, after her speech to a Conservative Party membership hustings. Getty

Mr Sunak speaks at the University of Exeter in south-west England. AP

A supporter of Ms Truss at a Conservative Party hustings in Exeter, south-west England. Getty

Ms Truss at a hustings event at the Pavilion conference centre at Elland Road in Leeds. PA

Mr Sunak in Salisbury watching a screening of the Uefa Women's Euro 2022 final between England and Germany at Wembley stadium. England won 2-1 in extra time. PA

Ms Truss before the Uefa Women's Euro 2022 final at Wembley stadium in London. AFP

Mr Sunak meets Tory members at Fontwell Park Racecourse. Reuters

Ms Truss at an event in Dereham, Norfolk. AFP

Mr Sunak in Ropley, near Winchester, Hampshire. PA

Ms Truss speaks as Conservative Member of Parliament Tom Tugendhat looks on at a Conservative Party leadership campaign event at Biggin Hill Airport. Getty

Ms Truss on the campaign trail in Woodford Green, on the outskirts of London. Reuters

Mr Sunak at a Conservative Party hustings event in Leeds. AFP

Ms Truss speaks at the hustings event in Leeds. AFP

Sunak and Truss-themed souvenirs at a stand during the Leeds hustings event. Reuters

Ms Truss, and her mother, Patricia, arrive for the hustings event. Getty

Ms Truss poses with supporters in Morley, England. Getty

Mr Sunak delivers a speech during a campaign event in Newmarket. AFP

Ms Truss and Jake Berry, MP for Rossendale and Darwen, during a visit to a broadband interchange company in Leeds. PA

Mr Sunak answers questions as he takes part in the hustings in Leeds. AFP

Ms Truss speaks at an event at a private house with members of the Conservative Party in Woodford Green. PA

Ms Truss and Mr Sunak pose for a picture before a BBC leadership debate at Victoria Hall in Hanley. Getty

Ms Truss addresses Mr Sunak during the televised debate. Getty

Mr Sunak, with daughters Krishna and Anushka, and wife Akshata Murthy, during a visit to Vaculug tyre specialists at Gonerby Hill Foot, Grantham. PA

Ms Truss speaks to people while campaigning in Marden. Getty

Ms Truss celebrates after being named, along with Mr Sunak, one of the final two candidates in the race to become the UK's next prime minister. PA

Mr Sunak outside his campaign office in central London. EPA

Ms Truss outside Downing Street in London. Reuters

Rishi Sunak meets Conservative Party members and activists, in Teesport, Redcar. Reuters

Conservative leadership candidates Mr Sunak, Ms Truss, Kemi Badenoch, presenter Julie Etchingham, Tom Tugendhat and Penny Mordaunt during 'Britain's Next Prime Minister: The ITV Debate' in London. EPA

Ms Badenoch arrives at Here East studios in Stratford, east London, before a live television debate. PA

Mr Sunak arrives at a London event to launch his campaign to be the next Conservative Party leader and UK prime minister. Reuters

Mr Tugendhat appears on the BBC One current affairs programme, 'Sunday Morning'. PA

Ms Badenoch, Ms Mordaunt, Mr Sunak, Ms Truss and Mr Tugendhat before the live television debate. PA

Ms Mordaunt arrives for the launch of her Conservative leadership campaign at the Cinnamon Club in Westminster. PA

Ms Truss speaks at the launch event for her campaign to become the next leader of the Tory Party and Britain's prime minister, in London. EPA

Chancellor of the Exchequer Nadhim Zahawi, one of the candidates who has been knocked out of the race, giving a speech at the Churchill War Rooms. PA

Former leadership candidate Jeremy Hunt appearing on the BBC One current affairs programme, 'Sunday Morning'. PA

Sajid Javid attending the launch of his campaign to be Conservative Party leader and prime minister, at the Cinnamon Club in London. He has since been knocked out of the contest. PA

Rehman Chishti is interviewed after announcing his bid to become the next prime minister. Mr Chishti is no longer in the race. Getty

Mr Tugendhat speaking at the launch of his campaign. PA

Culture Secretary Nadine Dorries and Conservative MP Iain Duncan Smith arrive for the Truss campaign launch event. Getty

Former leadership candidate Attorney General Suella Braverman at the Churchill War Rooms in central London. PA

Supporters of Mr Sunak wait for his arrival ahead of the campaign launch. Bloomberg

Mr Tugendhat makes a speech at the launch of his campaign. PA

Mr Javid mops his brow while launching his campaign. Getty

Ms Truss leaves for work after her announcement that she would be running for the leadership of the Conservative Party. Getty

But the Sunak campaign will be hoping the extra time to make their case before the first votes are cast will be in their favour.

The Truss campaign spent Tuesday in damage control after abandoning a policy to slash £8.8 billion ($10.6bn) from public sector pay outside London.

The announcement on Monday night met fierce opposition from senior Conservatives who said that it would be “levelling down” the nation by leaving nurses, police officers and teachers worse off.

Conservative Tees Valley mayor Ben Houchen, who is backing Mr Sunak, said the pay policy had left him “speechless”, and suggested it would have cost the party the next general election if introduced.

Mr Houchen told BBC Radio 4 that the “horrifically bad” policy “could be Liz’s dementia tax moment”, in a comparison to Theresa May’s scrapped policy that was blamed for her poor electoral performance in 2017.

Everything you need to know about Liz Truss - video

Mr Sunak’s camp argued that the move was no mistake, saying Ms Truss had called for the move when she was chief secretary to the Treasury in 2018.

But Ms Truss insisted her policy had been “misrepresented”.

“I never had any intention of changing the terms and conditions of teachers and nurses," she told the BBC in Dorset.

“But what I want to be clear about is I will not be going ahead with the regional pay boards, that is no longer my policy.”

Former chief whip Mark Harper told Ms Truss to stop “blaming journalists – reporting what a press release says isn’t ‘wilful misrepresentation’.”

“So this U-turn has wiped out £8.8bn in savings. Where are these going to come from now?” Mr Harper asked.

“An economic policy that can’t be paid for isn’t very Conservative. Mrs Thatcher would be livid.”

Everything you need to know about Rishi Sunak - video

But after a mixed day, Ms Truss did receive a campaign boost with backing from the Daily Mail.

“Members are making up their mind and they are supporting Liz," a Truss campaign source said on the YouGov polling.

“Her bold and ambitious plan for the country and economy is uniting Conservatives right across our nation.

"But we are certainly not complacent, Liz is fighting for every vote, meeting as many members as possible.”