Brown's future on the line as he faces Glasgow by-election meltdown

Gordon Brown's attempts to avert a shattering by-election defeat were floundering last night after a weekend of party chaos.

Labour was left struggling to find a candidate for the July 24 election in Glasgow East, a normally safe seat for the party that is at risk from the Scottish Nationalists.

Amid accusations that the turmoil had led to an embarrassing 'lost weekend' for the Prime Minister, Labour figures predicted last night that Mr Brown would be forced to quit if he lost a contest in his own backyard.

Labour's campaign was plunged into turmoil on Friday night when the candidate earmarked by Mr Brown to fight the seat pulled out unexpectedly.

George Ryan failed to turn up for the selection meeting, citing family reasons for his decision to withdraw.

The local councillor was the runaway favourite, but backed out amid reports that questions were being asked about his alleged involvement in a benefit fraud.

Mr Brown, who has personally lobbied prospective candidates in an attempt to secure a heavyweight for the seat, was forced to scramble to find a replacement.

Yesterday it emerged that Margaret Curran, the party's health spokesman in the Scottish parliament, is likely to be confirmed tonight as the candidate.

The confusion has given the other parties a head start in a contest caused by the sudden retirement on health grounds of sitting MP David Marshall.

On paper, Glasgow East is Labour's 25th safest seat in the country. The party held it with a majority of 13,000 in 2005 and a mammoth 60 per cent share of the vote.

But with Mr Brown's popularity in freefall, the SNP led by Alex Salmond is homing in on what could prove to be a decisive contest.

Senior Labour figures warn defeat could be the tipping point that would trigger concerted attempts to remove Mr Brown as leader.

The Labour high command deliberately called a snap by-election to wrongfoot the SNP, which does not have a strong organisation in the area.

Voting will take place two days after the Commons rises for the long summer recess, when many MPs who might otherwise plot against Mr Brown will be on holiday.

The chaos over the selection will have further hit party morale already fragile after the resignation of Wendy Alexander last month.

The party's leader in the Scottish parliament stood down suddenly after being hit with a one- day suspension for accepting an unauthorised foreign payment to her election campaign last year. Former Labour spin doctor Lorraine Davidson said: 'I think it's as simple as this: if Labour loses the Glasgow East by-election I think Gordon Brown is finished.

Election challenge: Margaret Curran could step in after George Ryan withdrew

'Because it basically means that anyone in the PLP (Parliamentary Labour Party) with a majority of less than 13,500 is going to say, "If Gordon Brown's the leader, we're
away as well". You're really talking the bulk of the PLP. It's complete and utter meltdown.

'So if Glasgow East is lost I think you will see a challenge to Gordon Brown. I just do not see how he can survive it.'

Mr Salmond claimed his SNP was off to a 'flying start' with its candidate, John Mason.
'Labour, by contrast, are in complete meltdown - both locally and nationally,' he said.

'This is their "lost weekend" - they don't have a leader in Scotland, they don't have a candidate in Glasgow East, and they have a Prime Minister who refuses to come to the constituency.'

Liberal Democrat campaign chairman Robert Brown insisted Labour had 'entirely lost its way'.

He added: 'Nobody knows what they stand for any more and, therefore, it is no surprise they are finding it difficult to find a candidate.'

Scottish Tory leader Annabel Goldie described Labour as ' rudderless at Westminster, leaderless at Holyrood and treating the people of Glasgow with contempt'.

But Mrs Curran said: 'I have decided to do this because I'm deeply committed to the communities of the East End of Glasgow.

'I am hoping to be the Labour Party nominee in order that we have a spirited campaign in the by-election.'

'Star of the North'                                                                 

Margaret Curran is one of the stars in Labour's troubled Scottish machine.

From tonight Gordon Brown's fate will be in the hands of the redoubtable community campaigner with a passion for opera.

She was raised in the East End of Glasgow, a Roman Catholic like a majority of her would-be constituents, and understands the area and its problems.

Her impeccable working-class credentials will be a vital asset in a downtrodden constituency and her family story testifies to the power of aspiration: one of her two sons has gone on to Oxford.

Mrs Curran, 49, was a minister in the Scottish executive until last year, and was seen as a contender to replace Wendy Alexander following her exit as Labour leader in the Scottish parliament last month.