In terms of "referrals," for years the "blue star" system has been implemented - whereby someone already working within the company would stick a blue star on a mate's application. The more blue stars, the more likely your application would be fast-tracked for an invitation to interview. However I think you'll find they're moving away from this practise, as they have had their fingers burnt in the past - mainly from taking on guys that really weren't ready to step up to a jet, and subsequently required a lot of additional training to finally get up to speed. Just one reason I'm sure why the new recruiting process now requires, amongst other things, a screening check in a B737 sim.
Nevertheless whilst the new process may be fairer in some ways, there is still the question of how to get your name on the list of interview candidates in the first place. On this note, I would reiterate what has already been said, in the context of making your application look as good as possible. And I'm not talking about just making sure your logbook hours add up nicely. It's been a very long time since I looked at the application format, and correct me if I'm wrong, but I do remember it asking a couple of questions such as "why do you want to work for
VB/what qualities can you bring to the role?" or something like that. As such, the quality of your answers might make all the difference (with correct spelling too whilst we're at it). Just my 50 cents' worth.