As the SNP eclipse deepens, tactical voting is being embraced - partially, at least - by Scottish unionists.
Last night's poll from Survation/Daily Record reverses the slow recovery of Labour's fortunes in a hammer blow to Ed Miliband's party.
Until now Labour were at least able to take comfort from the fact that the SNP's huge advantage north of the border was slowly being reeled in.
Not in March, the latest research suggests. Survation has the SNP up two points on 47%, while Labour is down one point to 26%. The three-point swing takes the nationalists' advantage to 21%.
The Conservatives are up one to 16% while the Liberal Democrats are down one to just four per cent. Others account for seven per cent, unchanged.
"Looking at least from a top-down view, the state of play in Scotland remains bleak for Labour with the SNP's surge remaining firm since Survation's polling indicated crossover for the parties some months before the independence referendum," chief executive Damian Lyons Lowe says.
Survation questioned 1,027 adults aged over 16+ online between March 12th and March 17th.
Today's polling follows Lord Ashcroft's research which suggested that the SNP could win all but a handful of Scotland's 59 parliamentary seats.
That led to a frenzy of meaningless Westminster reporting about whether Ed Miliband would rule out going into government with the nationalists. The Labour leader duly obliged - despite the fact both parties believe the far likelier scenario is that Scottish MPs could support a Labour minority government in keeping with their ambition to support a 'progressive' government in London.
Faced with a surge of SNP support that threatens to have a decisive impact on the makeup of the next government, Scotland - always a part of the UK ripe for this sort of thing - has seen an outbreak of tactical voting in recent weeks.
"If you don’t want that then the only way to stop the nationalists is to vote Lib Dem in this constituency," the endangered chief secretary to the Treasury, Danny Alexander, told the Scotsman on Sunday this weekend.
"Labour and the Tories are way off the pace and they don't have a hope of winning."
There is nothing new in the Lib Dems squeezing other parties' votes; they have never let their opposition to first-past-the-post get in the way of the practical fact that 'winning here' means persuading people who naturally prefer other parties to vote their way.
But in Scotland, everybody is doing it. Even socialist Tommy Sheridan, who thinks the SNP deserve to be supported by left-wingers.
"For the first time in our lifetimes the SNP could actually win a Westminster election in Scotland and send a clear independence, anti-Trident and anti-austerity message to the heart of the British establishment," he said.
"This is an historically unique election. It demands a unique tactical response."
Fringe parties like Sheridan's Solidarity outfit aside, the bulk of tactical voting is against the SNP. Take Dumfries and Galloway, where Russell Brown held the seat for Labour in 2010 with the SNP in third place. His re-election was "one of the biggest swings to Labour in the UK", his website proudly states. But now he is down in third place himself, the local Conservatives are pointing out.
Some are even trying their hardest to push tactical voting against the SNP to a whole new level. The Scotland's Big Voice campaign has even produced its own definitive list of how to vote, wherever you are, to best thwart the SNP.
Despite all these efforts, and as today's Survation poll underlines, the SNP's lead may be too big for tactical voting to make any real difference.
As the Number Cruncher Politics blog has pointed out, the SNP only has a single-digit lead over Labour in 15 seats - and in just two of them is the lead less than five points. The Lib Dems look like coming in third rather than second, and the Tories only seem plausible in the trio of seats in Scotland's extreme south.
Effie Deans, a tactical voting fan in the seat where Alex Salmond is hoping to get elected to parliament, accepts there are problems but thinks squeezing has to be done anyway.
"In the end if we can't cooperate to defeat Salmond in Gordon, we may as well give up cooperating at all," she writes for ThinkScotland. In that case I'll campaign for my party, you campaign for your party, we'll split the No vote and the SNP will be the winners."
She thinks the 'No' vote can be united to deny the SNP the 50-odd MPs it looks on track to win. Looking at the numbers, reinforced by today's Survation poll, her optimism about the powers of tactical voting don't look very realistic.