A Labour MP is on the verge of defecting to UKIP, Douglas Carswell claimed today.

The former Tory MP who easily won the Clacton by-election after switching parties said it was 'looking very promising' that a Labour MP would be next to join him.

Labour leader Ed Miliband today sought to rescue his crisis-hit leadership with a fresh promise of an immigration crackdown, after UKIP also came within 617 votes of winning the safe Labour seat of Heywood and Middleton on Thursday night.

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Ed Miliband (left) has announced new immigration measures after conceding UKIP is a threat to the Labour party, but new UKIP MP Douglas Carswell, pictured arriving at the BBC today, claims a Labour MP could be next to defect

Mr Carswell's surprise defection in August sent shockwaves through Westminster, and within weeks was followed by fellow Mark Reckless, the MP for Rochester and Strood.

Attention had been focused on Tory MPs and their willingness to change parties, fearing a UKIP surge in their constituencies would cost them their seat in Parliament.

However, the Heywood result and growing unease about Mr Miliband's leadership mean UKIP leader Nigel Farage now has his sights set on wooing Labour MPs to cross the floor.

Mr Carswells revealed that within hours of his Clacton by-election triumph, he took a call from a Labour MP poised to jump.

Speaking on Friday, he said: 'A member of the parliamentary Labour party called me this morning and we had a chat about them coming over.

'It's looking very promising,' he told The Sunday Times. 'For years and years and years, like monopolistic businesses, they assumed the customers had nowhere else to go.

'MILIBAND NEEDS A BROWN AND A PRESCOTT OR HE WON'T WIN' Ed Miliband has been urged to copy Tony Blair by having people with broader appeal around him, such as Gordon Brown and John Prescott Ed Miliband must get out of his 'north London comfort zone' or he will not win the election, Labour MP John Mann warned today. He urged the Labour leader to appoint a wide slate of MPs to his frontbench, in the way that Tony Blair put up with Gordon Brown and John Prescott because they broadened New Labour's appeal. Mr Mann said Mr Miliband’s article would not persuade a sceptical country he was taking action to deal with immigration. Labour MP John Mann He told MailOnline: 'We need to see demonstrable evidence of a change of attitude. 'He has to move outside his north London comfort zone. Tony Blair had Brown, who he clearly couldn’t stand, and Prescott, who is not a natural dining partner, as his key lieutenants. 'Blair’s wasn’t particularly comfortable with either Brown or Prescott but he understood that represented areas of the electorate that he didn’t feel comfortable with. ‘Miliband isn’t doing it, that’s Miliband’s problem. ‘If he doesn’t succeed in getting outside his comfort zone, he will not be Prime Minister.' Advertisement

'Then UKIP came along. For years and years they assumed that their own party had nowhere else to go. Well, guess what, guys, they do.'

Today he told BBC One's Andrew Marr Show he hoped there would be more Tory MPs joining UKIP.

But he stressed: 'UKIP is not the Conservative party in exile. I try to work with MPs from all parties. I am primarily interested in making sure voters make the journey I have made.'

He refused to confirm or deny that veteran Labour MP Austin Mitchell was poised to defect.

'Austin Mitchell has been saying that for many years and on that I think he's proved ahead of his time,' Mr Carswell said.

'I try and work with MPs of all parties but I'm primarily interested in trying to make sure that voters make the journey that I have made.

'This isn't about which 650 politicians make their journey.'

He likened the Tory party to struggling music shop HMV, with UKIP acting like the online music-streaming service Spotify.

'I think it’s a little bit like HMV music, once ubiquitous when it came to buying music.

'The way the Tory Party is retailing politics is like the way HMV retailed music: it’s a defunct retail model.

'I argued that we needed to Spotify politics, we ought to make the Conservative Party a bit more like Spotify, but the Conservative Party can’t change and won’t change because there are too many vested interests that are against recall, against open primary, against direct democracy, against change.

'Why? Because if we had direct democracy many members of the Conservative Party and the leadership would be replaced.'

In an attempt to shore up his troubled leadership, Mr Miliband today pledged tougher measures for migrants coming to Britain saying they will have to be able to speak English and must earn the right to claim benefits.

The Labour leader announced the policy just days after the party only narrowly won last week's Heywood and Middleton by-election in the former Labour stronghold, where it hung on with a wafer-thin majority over Ukip.

Mr Miliband has been accused by some party members of not doing enough to combat the threat of Ukip with Andrew MacKinlay, the former MP for Thurrock, saying the party's dismal performance 'was not the performance of a Government-in-waiting'.

But today writing in the Observer, Mr Miliband says he recognises that Ukip is a threat that the Labour party cannot ignore as immigration has 'changed the face of many communitites.'

He then went on to explain the new immigration measures were an attempt to tackle the issue in a 'hard-headed fashion'.

The paper reports that sources say the new measures would include extending the period that EU migrants must wait before they can claim unemployment benefits to six months and imposing language tests on those applying for certain public sector jobs.

Mr Miliband wrote: 'Our task is to turn the despair and cynicism on which Ukip thrives into a positive force for change. We can only do so if we understand that many people are turning to Ukip because of disappointment with Conservative and Labour governments.

'I will not cede the issue of immigration to those offering fear or falsehood. So I will continue to chart a new way forward, combining stronger border controls and laws to stop the exploitation that has undermined wages of local workers, with reforms to ensure those who come here speak English and earn the right to any benefit entitlements.

'Such measures are part of a compelling and credible plan for Britain's future that will restore the values people believe in – contribution, responsibility, fairness – to the way our country is run.'

Ukip have risen dramatically in the polls since April 2012 when they languished on 9% with little hope of an MP

The pledges come after concerns Nigel Farage and UKIP are gaining massive support in traditional Labour heartlands.

Labour deputy leader Harriet Harman today insisted there was no 'wobble' in the Labour ranks and denied a leadership change would be required despite concerns about how voters view the party and huge Ukip gains in Heywood and Middleton.

She told BBC 1's Andrew Marr Show: 'There's not a wobble in the ranks and nor should there be.

We are not going to have a wobble or a leadership change Harriet Harman, Labour's deputy leader

'Obviously we're very pleased we've got a new Labour MP and it was evident there was a collapse in confidence in the Tories and the Lib Dems but that doesn't make us complacent because the result was very close.

'But I think what is absolutely evident is that the anger and concern that there is amongst people when they're being told the recovery has arrived and yet they're not getting better off, and feeling disconnected from politics, that is being picked up on by Ukip but actually Ukip, although they're tapping into that sense of despair, they don't provide the answers.'

Asked if there was any chance that Labour would change its leader before the general election, Ms Harman said: 'No, absolutely not. We always knew and Ed Miliband knew, the whole party knew it would be a very tough challenge after we were defeated in 2010 to be in contention to be in government and to have a Labour prime minister in 2015.'

She added: 'We are not going to have a wobble or a leadership change.'

Labour MP Graham Stringer says Mr Miliband's team have now idea how to combat Nigel Farage's, pictured, 'street fighting' political skill

One northern Labour MP, speaking on condition of anonymity, told the Mail on Sunday: 'If Miliband cared to ask me, I could tell him why Ukip is picking up votes in northern constituencies. It is because if a single mother with a child is in a queue for council housing, she will find that an East European family with three children can jump ahead of her.

'And if she goes to the local GPs, the same East European families will have taken all the appointments. Anyone who utters that kind of sentiment is denounced as a racist. It is nothing of the sort: it is the truth.'

Meanwhile another MP, Graham Stringer, said Labour could lose the General Election because Mr Miliband's team had no idea how to combat Nigel Farage's 'street-fighting' political skill.

Mr Stringer, who took part in the Heywood campaign,said he was shocked by the hostility to Labour on the doorstep.

'We came extremely close to losing the seat,' he said. 'The ministerial bag-carriers who now run the Labour Party have no idea how to manage the bare-knuckle street-fighting which is Farage's speciality.

'The seat nearly fell – and the General Election could be lost for the same reason – because we are not tackling people's feeling of unfairness over immigration and the effect it is having on schools, housing and hospitals.