YouGov’s latest set of leadership ratings contains cautiously promising news from the Liberal Democrats: Vince Cable has the best (least worst) ratings of the three main UK party leaders.

Do you have a favourable or unfavourable opinion of the following…?

Vince Cable: net score -20 (favourable: 23%, unfavourable 43%, up from -22% in early May)

Jeremy Corbyn: net score -30 (favourable: 28%, unfavourable 58%, down from -26% in early May)

Theresa May: net score -37 (favourable: 25%, unfavourable 62%, down from -21% in early May)

As ever, apply caution to one poll, especially as the 23% favourable matches rather than exceeds Vince Cable’s previous best on that specific figure, and although I’ve used ‘up’ and ‘down’ pay caution to the margins of error when it comes to comparing polls too.

Even so, it’s a positive straw in the wind and helps explain the run of positive council by-election results: the national political tide isn’t flowing in the party’s favour, but it is at least not flowing against. That shift in the party’s national position doesn’t deliver local victories, but it does make it easier for local teams to deliver such victories.

By contrast, while Vince Cable’s ratings are higher than the favourable/unfavourable net score for the Liberal Democrats, both Theresa May and Jeremy Corbyn have net ratings worse than their own party.

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