Liberal Democrat by-election wins come with a puzzle

The Lib Dem shift in approach to campaigning is happening against a cautiously promising uptick in the Liberal Democrat electoral fortunes.

Stripping out the statistical noise from individual polls, the party's polling ratings have risen slowly through the second half of 2016. The volume of polls and extent of the trend means the small movement is heading towards statistical robustness, but is of course only a small political step.

In December, post-Richmond, moreover the Liberal Democrats averaged over 10%. The last time the party was averaging in double figures was September 2013. Of course, rejoicing at being in double figures says more about how low the party sunk than about how far it has bounced back.

Both Ukip and Labour have continued to slide, with the Conservatives continuing to rise (reinforcing Matt Singh's point that the Conservatives look to experiencing more than just the usual honeymoon for a new leader).

Why is this? It's a subject short, so far, of detailed analysis but an important one for the future direction of the Liberal Democrats.
So here are some preliminary thoughts on the explanation:

• As the SNP demonstrated in 2015, a losing share in a referendum can still be a landslide-inducing share in a multi-party first past the post election. That only goes so far as an explanation given the vote shifts in the above chart, and indeed the number of Liberal Democrat wins with well over 50% of the vote in Leave areas.
• However, turnout in local elections, and all the more so in council by-elections, is far lower than it was in the European referendum. A losing share locally in the referendum can easily translate into a winning share, even one over 50%, in a lower turnout election.
• Moreover, in lower turnout council by-elections, there's a premium on the benefits from local organisation. The Liberal Democrat organisation has been on a huge upswing courtesy of the surge in party members. For the Conservatives, the long years of decline were masked by the massive spending of central funds in the 2015 general election. A blip in Conservative membership on Theresa May's ascension does not appear to have turned into a revival in grassroots organisation. (For Labour, meanwhile, the surge in membership has not produced a surge in people wanting to campaign in by-elections, as most notoriously illustrated by the Lib Dem gain from Labour in Sheffield on a huge swing on the same night as a Momentum phonebank elsewhere in the city was keeping Labour members busy on internal campaigning.)
• That Liberal Democrat organisational edge has been aided by a string of remarkably good local candidates, deeply rooted in the communities where they have secured large swings. This partly comes from having so many new members and also is a result of the large number of good ex-councillors there are in many areas: people who lost their seats during coalition but are now once again up for getting back on their council.
• The winning council by-election campaigns have also been able to appeal to many soft Conservatives. Both qualitative feedback from doorstep conversations and also more rigorous quantitative analysis of canvassing returns have shown in a variety of contests a good slug of Conservative Leave voters switching to the Liberal Democrats. Often these are voters who want the UK to remain in the Single Market with a soft Brexit (a third of Conservatives want a soft Brexit), and so are happy to vote for a party clearly opposed to a Hard Brexit and opposing the Hard Brexiters in the Tory leadership. The other factor appealing to such voters is a resumption of 'normal' politics, with the Liberal Democrats reverting to what they have long been - the natural opposition to Conservative council administrations across much of southern England.

Most of those points offer the possibility of the Liberal Democrats continuing to make council gains without having to particularly base that appeal on Remain voters.
It's certainly helpful to be able to have a wider appeal, but it would be a mirage to think therefore that a durable, robust Liberal Democrat recovery does not have to be rooted in appealing to Remain voters - and more generally, to be based on winning over people who share the party's values rather than those simply most attracted by Lib Dem assiduousness in addressing local potholes.
That's because as important as the latter group are, they are susceptible to swinging away again from the party in the face of other hard-working campaigners from different parties - or in the face of the political pressures such as a hung Parliament.
Hence the case which David Howarth and I have made for building a stronger Liberal Democrat core vote. On which note, it's time to report on my survey of party members...