Whether or not key ministers whose constituencies are affected by HS2 turn out to vote at today’s second reading of the legislation introducing it, the bill will pass this stage with a big majority thanks to cross-party support. Between 20 and 30 MPs are expected to defy the whip and either vote for a motion declining to give the Bill a second reading, or against the second reading itself.

What will be interesting over the next few months is how many concessions critics of the Bill are able to eke out of the government, and whether this buys them off or not. When I spoke to Cheryl Gillan about her proposals for a longer tunnel under the Chiltern area of outstanding natural beauty, she told me that ‘I’m not changing my position on the basis of that in any way, shape or form. I’ve always had a twin track approach saying I don’t think this is the best project but I’ve also got a duty of care to my constituents.’

But some of the changes that have already been made have been part of an attempt to seal in Labour support for the project. Some Tories, though, worry that this support is still not guaranteed, and that Labour could outflank them by dropping HS2 at an opportune moment and pledging to spend the £50bn on something else. Key rebel Andrew Bridgen tells me:

‘I’m still fairly convinced that Labour are going to take the £50bn in the pot if the polls are close. it’s a no brainer, there’s no point to Labour without money to spend, and where’s the money? It’s irresistible to Ed Balls, it’s like leaving a vampire in charge of a blood bank and it works because so many people don’t want it. With that £50bn Balls could buy off the Northern cities.

‘Politically if we haven’t got a plan for what we’re going to do with that money, we’ll suffer. You can buy a lot of votes in marginal seats. It works on every level to ditch it.’

Balls is, as Coffee House revealed on Saturday, going to vote in favour of the legislation this afternoon. And the Conservative party are hardly going to tell their backbenchers that they do have a contingency plan to spend a spare £50bn if Labour do pull out, even if Andrew Bridgen has pledged his loyalty to the Prime Minister of late.

Tags: Andrew Bridgen, Ed Balls, High-speed rail, HS2, UK politics