Bigot-gate is raging on this morning and it could not have come at a worse time for Gordon Brown, ahead of tonight's crucial, final televised leaders' debate.

For those of you who have managed to miss it, Brown basically called Rochdale widow a "bigoted woman" during a discussion in his car which was picked up by a Sky News microphone that he had been wearing for a walk about.

The woman in question, Gillian Duffy - a life-long Labour voter apparently - had tackled him in the street on a series of issues, including immigration.

What followed was something that wouldn't look out of place in Armando Iannucci's fantastic The Thick Of It.

Brown was played the clipped while appearing on Jeremy Vine's radio show, Peter Mandelson and various other Cabinet members were dispatched to radio stations to defend the leader, who apologised firstly on the phone to Mrs Duffy, then on the TV and finally at her home.

Cue the best live TV in decades (notice the sarcasm) which basically consisted of Mrs Duffy's front door, flanked by a couple of plain-clothed police officers while "experts" back in the studio talked over the top.

You have to feel sorry for Brown.

What he said he can't be defended but then I guess he didn't realise he still had his mic on and that the TV channel in question - which just happened to be Murdoch's Sky News - would use it.

That said he was naive to think that Sky News wouldn't use the clip and I have to say I don't blame them.

It was political dynamite and unfortunately for Brown only he can take the blame for igniting it.

If tonight's debate was going to be interesting before yesterday's events, its going to be fascinating now.

One bookmaker is offering odds on the number of times the word bigot is mentioned and if I was a betting man, I'd be having a little flutter to spice the evening up.

I will be tweeting throughout tonight's BBC debate via my Twitter account and will be uploading my initial thoughts straight after the leaders have finished right here.

And, as I do every week, I'll be providing a fully analysis tomorrow morning in my blog.

To follow me on Twitter, log onto www.twitter.com/AndrewGreavesBN