Each week they would fight for votes through varying different rounds. I believe one was something about not being aloud to say no and if you did the turn was over. There was a quick-fire round at the end aswell that was basically telling party policies to win votes.
I remember a paticularly funny one with Griff Rhys Jones in it (ft. here in 'Smith and Jones' and 'Not The Nine O'clock News'. Griff was on Graeme Gardens team and was given something to read out as a party political broadcast. This happened to be the song 'Raining Men'- he read it out so seriously and so much like a party broadcast it was hilarious!