We’ve had our first bumper night of Constituency Labour Party nominations, with almost as many CLPs (21) nominating tonight alone than across the rest of the contest combined (27). Most dramatically, Lisa Nandy has picked up six nominations, taking her to a joint-second place

The underlying story, still, is Keir Starmer’s strength

Keir Starmer continues to have a big lead – both overall (he has 31 CLP nominations, more than the rest of the field combined), and tonight itself (he has 13, also more than the rest of the field combined). It’s impossible to build a data-driven case as it stands that anyone else would win the Labour leadership election were it held tomorrow. But, of course, the leadership election is not being held tomorrow!

Lisa Nandy’s performance tonight could just be luck

What about Lisa Nandy’s six nomination haul tonight? Is it a sign of a genuine surge or just good luck?

As I wrote at the start of this stage of the contest, it’s probably more useful to see the CLP nominations stage as probabilistic rather than definitive. If you pulled 100 Labour members off the street in 2016, you’d have expected 60 of them to be backing Jeremy Corbyn. In most CLP meetings, that dynamic played itself out as you’d expect – but in a minority of them they didn’t.

Nandy’s haul of just one CLP out of 27 going into tonight’s nominations was lower than it ought to have been. It may be that what we’re seeing tonight is just the nominations levelling out, and that by this time tomorrow Long-Bailey is back in second place.

Nandy and Starmer could be having their performances exaggerated

In 2015, Jeremy Corbyn ended up with more CLP nominations than anyone else but with less of a lead than you might expect given his huge victory over Andy Burnham, Yvette Cooper and Liz Kendall.

This happened for two reasons. The first was that for the first few months of the contest, while Jeremy Corbyn was always ahead among members overall, Andy Burnham was putting up a strong fight, though he fell away badly after the Welfare Bill vote, when the other three candidates abstained while Corbyn voted against.

The second, which endured all the way through, was that Corbyn was the least “transfer-friendly” candidate. Under Labour’s preferential voting system, members rank candidates in preference order. If their first choice is eliminated, their second preference is reallocated and so on until one candidate received more than 50 per cent of the vote.

Corbyn rarely got more than 10 per cent of all available transfers from Yvette Cooper and Liz Kendall, and so he would frequently lead in the first round of voting in individual CLPs and then lose overall.

Rebecca Long-Bailey is also less transfer-friendly than Keir Starmer or Lisa Nandy. This is likely underestimating her overall strength a bit.

However, I think Lisa Nandy is gaining support in a meaningful way

My impression, though, is that Nandy is genuinely picking up support, thanks to her strong performances in the media, and a tactically astute campaign that has seen her pick up the support of some of those planning to back Jess Phillips, some supporters of Rebecca Long-Bailey who think she is the most leftwing candidate who can win, and some of those who were backing Starmer who think that Nandy is the most electable candidate.

I don’t know how sustainable that coalition is but it is a real and growing one.