Over the past twelve hours my social media feed has been lit up by (over)-excited Lib Dems, blown away by a single YouGov poll showing the party up four on 15%, in a statistical near dead-heat with the Conservatives (18%) and Reform (17%).  

The prospect of a three-way battle for second place in the popular vote – were it to be sustained – might tickle a commentariat struggling for much to say in a campaign which, to all intents and purposes, feels over.  But how seriously should this one poll be taken and what should the Lib Dems actually be excited about?

The first and most obvious thing to say is that, if one poll is out of line with all the others, it is probably just wrong.  Don’t believe a single poll because it tells you what you want to hear.  Wait for the trend across different polling companies using different methodologies.  One in twenty polls will just be wrong anyway and we’ve had a lot more than that during this campaign already.   Most likely YouGov’s poll is an outlier …

However, this poll may be wrong and still telling us something useful.  Its fieldwork was done on the day of and the day after the Lib Dem Manifesto launch.  As a result, the party received far more publicity than it normally does: 13,000 broadcast mentions.  

Being in the media is not of itself a guarantee of a poll bounce (just ask the PM about D-Day), but, for smaller parties, a manifesto launch is their chance to shine.  Assuming there are no disasters – and the Lib Dem manifesto coverage was very largely positive – then simply the chance to remind voters of your existence is a massive boost.  (The same might be true of the Greens for polls taken today and tomorrow, although they risk being drowned out by Sunak’s ITV interview and the Sky Leaders’ Debate.)  

Returning to the Lib Dems, however, the publicity around their manifesto will soon be swept away by the next election news, not least the other party manifestos – it won’t last. 

Optimistic left-wing commentators suggest that the sudden surge in Lib Dem support is evidence of the tactical voting message cutting through in blue-yellow marginals.  They point to the parallel decline in the Labour vote as evidence of this.   This, I’d suggest, is plainly nonsense: there simply aren’t enough such seats to generate such a surge.  Nor is there a reason why tactical voting would suddenly kick-in over a specific 48-hour period in the middle of a campaign, rather than gradually, as voters identify how best to vote in any specific seat to achieve their desired outcome.

So, I anticipate that, for the moment at least, this poll will be a high watermark for the Liberal Democrats, but it is nevertheless good news for them, feeding an existing narrative of a successful campaign and producing yet another bar chart which shows the party as the official Opposition.  

And this is the story which might yet play out in the election campaign.   For Ed Davey to become Leader of the Opposition, under FPTP and in the current circumstances, the Lib Dems need barely rise beyond their current 10% poll rating – as long as the Conservative vote remains evenly spread across the country and at around the 20% they are currently recording in Sky’s poll tracker, which is based on not one but all election polls.

A week is a long time in politics, so the cliché goes.  For a week now the Conservatives have been attempting and failing to move the media on from the D-Day debacle.   If – over the course of the next week – the polls continue to show the Lib Dems slugging it out for second place with the Conservatives  – not in the popular vote but in terms of seats – and the popular assumption remains that the latter’s campaign is in freefall, then I expect the question of who will come second to become part of the media narrative, with the very real risk for the Conservatives that it becomes a self-fulling prophesy.   

And that, rather than a single outlier poll, is what should really be getting the Lib Dems over-excited.