Mark updates his campaign diary after the row on the Politics Show between the two potential leaders of the Liberal Democrats.
Nick Clegg took issue with the title of Chris Huhne's document
How can they get their campaigns back on track, and what do they need to do in their appearance on Newsnight?
What a difference a few minutes of television can make.
The Liberal Democrat leadership campaign exploded into life on Sunday's Politics Show, as Jon Sopel caught both candidates by surprise by revealing the now infamous "Calamity Clegg" document live on air.
This consisted of a few sides of A4 purporting to show that Nick Clegg had flip-flopped on a range of policies.
But the controversy was not so much about the content, as its ill-judged title.
Spin versus substance
Just as Chris Huhne appeared to be building up some much-needed momentum, this sent his campaign into a spin.
He swiftly distanced himself from the title of the document - but stood by its contents.
His campaign team sought permission from party officials to circulate the document under a more anodyne title.
Judging from the latest statement on Chris's website, such permission has been refused - or the Huhne camp have thought better of it.
Some Lib Dem members may take the view that he didn't act decisively enough on Sunday afternoon.
Re-building their relationship
I had a minor concern that my presentation on Sunday's programme - which portrayed the leadership contest as a boxing match - may have been a little too combative.
But nothing could have been further from the truth. The scrap that ensued made great television - but showed the LibDems in a deeply unedifying light.
Chris Huhne said Nick Clegg had changed his mind on key policies
The party will hope that the clash on Tuesday's Newsnight is more even-tempered.
Chris Huhne will need to put in an excellent performance to get his campaign back on track.
And the concern for the Lib Dems is that whoever now wins - and the events of the last few days help Nick Clegg significantly - a way needs to be found for both men will to build a good working relationship.
The Liberal Democrats used to be seen as the nice party - a somewhat patronising label.
They now have a real challenge in trying to shake-off the label of being Britain's nasty party - an unhelpful tag that is starting to stick.
The Politics Show is on BBC One at 12.00pm on Sunday, 25 November 2007. You can reach the programme by using the form below.
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