It really is extremely tight. It would be foolish to make a guess on which way it will go.

What we do know might happen tomorrow is rather than there being a thumbs up or thumbs down vote to the deal, there could be an attempt by some MPs to bring in what they see as an insurance policy.

This could mean another delay in case this deal falls through in the next couple of weeks.

That is potentially being put forward as an amendment so MPs will have a chance to vote on it.

Without going in to all the potential machinations it could mean tomorrow turns, not just into MPs giving an opinion on Boris Johnson's deal, but also wrangling again about a potential delay.

This could make things more fuzzy, and certainly more frustrating for Downing Street.

It will be a showdown of sorts.

It is only a week since Downing Street began seriously to believe that they might get this deal over the line.

But they always knew that Parliament would be a very tricky hurdle.