China GDP: 8.3T (2012)
Brazil GDP: 2.5T (2012) Russia GDP: 2.1T (2012)
India GDP: 1.9T (2012)
India isn't even in the same league as China. India has to compete with Russia/Brazil. BRIC is an old grouping from years ago.
Having a huge population and being democratic doesn't automatically give you a bigger economy. Look at South Korea (1.3T) or Japan (6T) comparatively.