Thanks for such a detailed reply. I've looked at the course thoroughly and although I understand what you are saying I'm absolutely sure this is what I want to do. I'm only asking for advice on how to write the statement as I'm currently on a gap year and so I want to make absolutely sure I nail the personal statement because if I miss out this time I haven't got another year to wait. From what you are saying I know what I'll talk about, seeing as it's more of a technique based course I'll take it more from that angle.
As it's a combined honours course at a well-respected university I am confident I'm not going to end up with a bad degree as there are always going to be opportunities within Politics, I just want to diversify my options into something I love should I leave university and decide that isn't the direction I want to go in. Seeing as I don't want to go all in with a media degree I think this is the best thing!
Thanks for your suggestions though, they really are helpful!