With the Alternative Vote badly behind in the polls, Labour's big beasts have turned negative. In an interview in today's Independent, Peter Mandelson dispenses with high-minded arguments for reform and urges Labour supporters to vote Yes to "damage" David Cameron. He says:
Labour supporters need to use their noddle and ask themselves why Cameron is fighting so hard for a No vote. He's fighting for his party's interests but also to protect his own leadership. Labour has a chance to inflict damage on both. Cameron has been forced to intervene, to turn it into an intra-coalition partisan scrap in order to mobilise Tory support and Tory-supporting newspapers.
It's an important intervention, not least because the referendum is likely to be determined by Labour votes. As I've pointed out before, while Lib Dem voters are overwhelmingly in favour of reform (83 per cent to 17 per cent) and Conservative voters are overwhelmingly opposed (84 per cent to 16 per cent), Labour voters are split exactly down the middle (50 per cent to 50 per cent).
The Prince of Darkness may hold little sway over the electorate but his call to give Cameron a bloody nose, if taken up by the wider Yes campaign, could yet shift some votes in the final days of the campaign.
It's a message echoed today by Alan Johnson, who tells the Guardian: "What Labour voters need to ask is who wants them to vote No most. It's the Tories. They are bankrolling the No campaign because they know they have most to lose from a fairer voting system."
It won't be long before the Yes campaign is accused of diving into the gutter but there's an important distinction to be made between negative campaigning, a legitimate political tactic, and telling outright lies, as the No to AV campaign has.
In reponse to Mandelson, we can expect the 125 Labour MPs calling for a No vote to point out that they, and not the Tories, would now suffer under AV. The most recent YouGov poll on the subject showed that while Labour would win a majority of 60 under first-past-the-post, this would fall to 34 under AV. But such psephological considerations are of little importance to the Machiavellian Mandelson. As he points out, a Yes vote would lead to Cameron being branded a serial loser by his own side:
Labour people need to question why Cameron is suddenly so desperate for a No vote. Because a Yes vote would send the Tories into convulsions and greatly weaken him. Right-wing Tories have already been gravely warning it would make Cameron a "lost leader". That is something Labour supporters should bear in mind as they consider their vote.
History teaches us that the Tories rarely tolerate losers for long.
Add to this the growing fear of an early election under FPTP, which a cash-strapped and policy-free Labour Party would struggle to win, and a Yes vote starts to look like the rational choice for Labour tribalists. It remains to be seen, however, whether all of this is enough to offset the party's overpowering loathing for Nick Clegg.