Labour's troubled preparations for the Glasgow East by-election have run into yet another problem - fear of voter confusion about the candidate's name.

Margaret Curran, who was selected on Monday night, has the same surname as one of her rival candidates, Frances Curran, of the Scottish Socialist Party (SSP). Labour's fears that it will lose votes to the SSP are compounded because its candidate will appear second to Frances Curran on the ballot paper.

Frances Curran said yesterday that she had already been mistaken for her Labour rival when out canvassing and will be working hard to ensure that there is no more confusion. “I don't want Margaret Curran's reputation for selling out. I kept my principles, she took the perks,” she said.

Frances Curran launched her campaign vowing that, if elected, she would take a “worker's wage” of £24,000 instead of a full MP's salary. “People have already had a go at me in the street because they think I'm Margaret Curran.”

Candidates are listed in alphabetical order on the ballot paper, which means that Frances Curran could top the list of those standing. The SSP took only 3.5 per cent of the vote at the last general election compared to Labour's 60 per cent, but Labour campaigners are worried that possible confusion could cost them votes in what will be a tight contest.

Already reeling from the chaos caused by the last-minute pull-out by its first-choice candidate, George Ryan, Labour is desperately trying to counter the potential for mix-ups by producing a mock-up of the ballot paper which will appear on its literature for the remainder of the three-week campaign. It will clearly show Margaret Curran's position on the list of candidates.

“We know this could be a problem but Margaret Curran is well-known by her first name in the area to the extent that she is even referred to in local newspaper headlines as Margaret rather than Curran,” a party spokesman said. “We are taking steps to make sure our voters know to look for our emblem on the ballot paper too.”

The ballot papers for the July 24 poll are to be printed in black and white, reducing the impact of Labour's distinctive red rose emblem. Glasgow City Council has also ordered polling station staff not to explain which Curran is which, even if asked.

David Miller, the election co-ordinator, said: “If someone asks which Curran is standing for Labour, my staff will not be allowed to tell them because they could be open to accusations of political interference. We will have a large mock-up of the ballot paper, which they will see before they go into the polling booth.”

The concerns over voter confusion were heightened by claims that the Shettleston part of the constituency had higher than average levels of spoilt ballot papers in last year's Holyrood election. Professor Bill Miller, of Glasgow University, said: “The situation would have been less confusing if it was the SNP and Labour candidates who shared a name because their names and logos are so distinctive, but Scottish Labour and the Scottish Socialists have overtones of being similar. However, I think any confusion over the names will be small and secondary to whatever else is going on in the campaign.”

Margaret Curran officially launched her campaign yesterday, challenging her SNP opponent, John Mason, to a TV debate. She also promised to consult voters over when they think she should stand down as an MSP if elected to Westminster.

The SNP. Tories and the Liberal Democrats challenged her to give up her Holyrood seat immediately, but she would only say that she would stand down in the “short term”. The Tories then joined forces with Labour to accuse the Nationalists of hypocrisy on the issue, pointing out that Alex Salmond, the First Minister and SNP leader, was an MSP and MP.

Margaret Curran also attracted fire over her apparent U-turn on the issue of an independence referendum. Echoing the position of the Scottish Labour Party, she said that she did not fear a vote, a stance that would put her at odds with Gordon Brown.

The SNP claimed that Labour was giving different accounts of Margaret Curran's views. “Last night we had David Cairns [Labour's campaign spokesman] saying Margaret Curran was not in favour of a referendum. Today the Labour candidate is saying she isn't frightened of the verdict of the Scottish people,” Bob Doris, MSP for Glasgow, said. “The different positions between Labour at Holyrood and Labour at Westminster make the Labour candidate's stance ridiculous and untenable.”

Labour, in turn, accused Mr Salmond of suffering a “Michael Howard moment” on BBC's Newsnight programme. Frank McAveety, MSP for Shettleston, said that Mr Salmond had failed to answer repeated questions from Jeremy Paxman on his commitment to keeping election promises. He said that Mr Salmond was asked ten times if the SNP would implement its manifesto promises - and ten times he refused to answer.

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