Quick Radio Button Question...

I've had a look in the Wiki but it doesn't seem to be mentioned... Is it possible for a radio button to be different colours depending on whether it's focused or not?

E.g.

blue when it's focused...




and white when a different button is focused...




Also, can I use a diffuse to determine the colour, that way when I go on to add colour schemes all the colours will change easily (i guess this applies to things like slider controls and spin controls as well).

Thanks