David Cameron is failing to reach out to voters in the north and Midlands, an ex-Tory frontbencher has told the BBC.
David Cameron is accused of not having wide enough appeal
Graham Brady said the Conservative leader was not making sufficient headway in the key battlegrounds which will decide the next general election.
Mr Brady, who quit as shadow Europe minister over the grammar schools row, said Mr Cameron's appeal was limited to urban liberal circles around London.
But Tory William Hague said Mr Cameron had "a very broad national appeal".
'Focus and tone'
Mr Brady told BBC Radio 4's The World This Weekend: "The changes David Cameron has made in the Conservative Party have been very successful in some places, and have been better at reaching out to a more liberal, metropolitan mindset.
"But they have not been making the same impact further away from London - in the north, in the Midlands, in places which really are an absolutely key electoral battlefield if we're going to win a general election.
"I think some of it is about the issues that David Cameron has chosen to focus more on, and some of it is about just tone."
BBC News political correspondent Guto Harri says Mr Cameron rejects the accusations and insists local election victories in the areas highlighted by Mr Brady prove his party can do well when it fights effectively on the centre ground.
Mr Cameron is also upbeat about his prospects of recovering his previous lead in the opinion polls, arguing that the shine will soon come off new Prime Minister Gordon Brown.
Tories need to target key electoral battlefields, says Mr Brady
Discontent has been voiced by sections of the Tory party over by-election performances and a surge of support for Mr Brown in the opinion polls.
"The media would like to see the Conservatives lose their nerve and go on a wobble," Mr Cameron told the Observer newspaper.
"But that's not what's going to happen. Opinion polls that go up are just as capable of going down.
"That's what happens in politics. These are just the storms you have to ride through in politics."
Shadow foreign secretary Mr Hague told BBC News 24, the Conservative leader was broadening the party's appeal.
"I don't think it is an appeal that is confined to the metropolitan areas. That is just not the evidence," he said.
Mr Hague, who has been given the task of rebuilding Tory support in the north of England, said: "You saw a really serious Conservative advance in the north of England in the local elections in May.
"Not universal across the north of England, but certainly the biggest advance we have made for very many, years. So I don't buy this argument that Conservatives can only make progress in certain parts of the country."
The former Tory leader added: "David Cameron has achieved wonders for the Conservative Party in the last 18 months and has been able to achieve things, as I can say with authority, previous leaders were not able to achieve over the last 10 years."
"We have a very strong and united team around him."
Meanwhile, one of the Conservatives' top donors, spread betting magnate Stuart Wheeler, has urged the Tory leader to be tougher on Europe and give a clearer commitment to tax cuts.
Mr Wheeler told the News of the World he still believed Mr Cameron could win the next general election.