Tony Blair and David Cameron were both dealt by-election blows in heartland seats last night.

Voters in Blaenau Gwent, South Wales, snatched by the late Labour rebel Peter Law at the general election after a row over all-women shortlists, failed to re-elect Labour in one of its former strongholds. Then the Tories almost lost Bromley and Chislehurst - one of the party's safest seats - to the Liberal Democrats.

In a further setback for the Prime Minister, Labour was relegated to fourth in Bromley and Chislehurst, behind the UK Independence Party.

Independent candidates won Blaenau Gwent’s seats in both the Commons and on the Welsh Assembly, leaving Labour without a majority on the latter.

The Bromley and Chislehurst contest in south-east London, which follows the death of the outspoken rightwinger Eric Forth, was the first major by-election challenge for Mr Cameron as Tory leader.

But the Tories’ 13,342 majority from last year’s general election slashed to less than 700, suggesting that Mr Cameron's move towards the political centre inhabited so successfully by Mr Blair might be turning off core Conservative voters.

A YouGov poll for The Daily Telegraph today declares Mr Cameron the public’s preferred Prime Minister over either Mr Blair or Gordon Brown, but it was Sir Menzies Campbell, the Liberal Democrat leader, who was the clear beneficiary of the result.

Sir Menzies said: "This is a stupendous result for the Liberal Democrats in one of the safest Conservative seats in the country. It shows that there is no confidence in Cameron’s Tories in the Conservative heartlands.

"Together with the results in Wales there has been a complete rejection of the Labour government following upon the Liberal Democrat success in Dunfermline earlier this year.

"Liberal Democrats are now challenging both Labour and the Conservatives, even in their heartlands."

But Mr Neill used his acceptance speech to round on the Lib Dems’ campaign tactics: "A minority of candidates, principally the Liberal Democrats, have chosen to fight this campaign with the most vigorous and underhand example of cynical personal abuse that I have encountered in 30 years of politics."

He told the Lib Dems: "If you sometimes wonder why it is that people in this country are turned off by politics, get a mirror and look at yourselves."

Labour's double defeat in Wales came in the constituency once represented by Aneurin Bevin and Michael Foot.

Despite a mammoth campaign by Labour that is believed to have cost at least £100,000, the people of Blaenau Gwent chose Dai Davies, a former steelworker, as their new MP and Trish Law, the widow of the constituency’s former MP, for the Welsh Assembly.

It was once the fourth safest Labour seat in Britain. Now the failure of the party to connect with voters in its heartland will send shockwaves through the party, reinforcing the fears that new Labour has been taking its core vote for granted.

The by-elections follow the death in April of Mr Law, the independent who stood and defeated Labour’s Maggie Jones, a trade unionist and friend of Cherie Blair, at last year’s general election. Mr Law, formerly a long-standing Labour activist, overturned the party’s 20,000 majority.

Shortly after his death his wife announced that she would stand for the Welsh Assembly, while Mr Davies, who was Mr Law’s agent, announced his candidature for Westminster.

Since then, Labour have bombarded the constituency’s valley towns with party workers and literature in an effort to recapture the seat.

Speaking last night, Mrs Law, who has no prior political experience, said that none of this impressed the people of Blaenau Gwent. "People have said in Blaenau Gwent they don’t want Tony Blair and they don’t want New Labour.

"New Labour is not doing Wales any favours and Blair is responsible for his own demise," she said.

She has not revealed whether she will fight the seat next year, when the whole of the Welsh Assembly goes to the polls.

Mr Davies said: "We have been dictated to by party politics but the Labour party machine has lost the plot. The socialist beliefs don’t belong to any political party; they belong to the people across the valleys."

Mr Davies stressed that his victory came despite the might of the Labour party machine. He spent £6,000 of his own money on the campaign, receiving just £800 in personal donations, and relied on a small band of supporters. By comparison, some households have received up to nine pieces of election literature from Labour.

The party also opened offices in four different towns in the area, and bussed in party workers and trade unionists from across the constituency for support.

The Labour Party’s candidate for Westminster, Owen Smith, a former £200,000-a-year lobbyist for Pfizer, appeared to stay away from the count for much of the evening.

Dubbed the "Oily Smith", the former spin doctor was the subject of some fierce attacks. One Labour source said: "Emotions are still running high following the death of Peter Law."

The result is also a personal blow for Mr Brown, who visited the constituency a fortnight ago, suggesting that the party had confidence they would win. Part of the Chancellor’s strategy in recent weeks has been to try and connect with traditional Labour voters who have felt alienated by Mr Blair.

Terry Page, who was supporting the Independent’s campaign, said that Labour had suffered a double wammy.

"The people of Blaenau Gwent said, yes, we will vote for both independents. We don’t like Blair and we don’t like New Labour. They have had a kick in the bum — again. We want Socialism back in the valleys in Blaenau Gwent."

Even some supporters of the independents admitted they had not expected Labour would get such a drubbing. "I’m quite surprised. I did think there would be tactical voting," one said.

RESULTS

Blaenau Gwent

Dai Davies (Ind) 12,543

Owen Smith (Lab) 10,059

Amy Kitcher (L Dem) 1,477

Margrit Williams (C) 1,013

Majority 2,484

Turn-out 50.5%

Swing 8.37% Ind to Labour

Bromley and Chislehurst

Bob Neill (C) 11,621

Ben Abbotts (LD) 10,988

Nigel Farage (UKIP) 2,347

Rachel Reeves (Lab) 1,925

Ann Garrett (Green) 811

Majority: 633

Turnout 40.45 per cent

Swing: 14.32 per cent C to LD

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