Yes, but it is a little more tricky than calling MPI_Bcast.
The prototype of MPI_Bcast as defined by the MPI standard is:
int MPI_Bcast(void* buffer, int count, MPI_Datatype datatype, int root,
This clearly prevents you from using a count larger than MAX_INT. However, you can build a datatype, by composing several types with counts under 1G and then use this datatype to do the bcast.