Backing up both partitions

I intend to use bootcamp to create a windows 7 partition. I am also going to need to back up that partition. I am backing up to an external hard drive (Westernut Digital My Book). The time machine is already set up and the Mac OSX side is fine on the back up. But I am going to need to back up the bootcamp partition. There is the whole Winclone thing which I don't really understand fully. I have this nice 2TB HD sitting next to me with plenty of space. Is there a way to back up both partitions to the same HD continuously? Like partition the External HD itself for each operating system. Or is that not going to fly?