Chris Mason: Real prospect of twists in leadership contest

Penny Mordaunt secured second place in the first round of voting

Six candidates left.

Forty-three votes - cast for the eliminated candidates - looking for a home.

And others, sensing that elusive thing momentum, or the lack of it, will probably switch too.

And round two beckons today.

The contest to be our next prime minister is being remoulded once again.

Jeremy Hunt - the man who finished second for the Conservative leadership behind Boris Johnson in 2019 - told me he's now backing Rishi Sunak.

And he hopes plenty of his supporters will too.

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Mr Sunak is well out in front and the working assumption is he will get one of the two golden tickets into the run off - the vote of Conservative Party members.

But the fizz and chatter, for now at least, is about Penny Mordaunt, the runner up in round one.

If she were to win this race, she'd be the most little-known prime minister on assuming office of modern times.

The challenge for the Foreign Secretary Liz Truss today, as she launches her campaign, is to prove later on that she is competitive and can grab a slot in the final two.

Her team reckon that what was described to me as her "natural ceiling" of parliamentary support is higher than Penny Mordaunt's.

They will also argue - as a former chief secretary to the Treasury - that she has more economic heft to take on Rishi Sunak.

But some on Penny Mordaunt's team rather archly think the more people hear from Liz Truss, the less they will warm to her and their candidate has a range, depth and personality Ms Truss can't match.

A few other things to keep in mind: the order in which candidates are knocked out, and not just who is knocked out, can have a big influence on how things shake out because of the reallocation of votes at each stage.

And what beckons after today is what one MP described to me as the "big realignment weekend".

It sounds like an expensive music festival, but they meant it would be the crucial moment where deals could be done, candidates could bail out, and support would start to solidify around the likely final pair.

Right now, it feels like Rishi Sunak plus either Penny Mordaunt or Liz Truss going on the ballot paper to party members.

But there are plenty more ballot papers at Westminster for crosses to be put on yet - and the real prospect of twists in this contest we haven't yet anticipated - and neither have the candidates.