OK well what did the person that whittled down the selection before you saw the one person left do. Of course you don't care when the vetting and choosing has already been done.
If you have the opportunity, getting your resume directly into the hands of a hiring manager is the biggest positive boost, bar none. But I recognize that having that option available or not is a matter of happenstance, on some big or small scale in one's life, more than anything else.
I am in the somewhat unique position where I can take those opportunities as they come as I'm earning money and staying afloat. I could stand to do more networking though.
It's a crapshoot, honestly. The internal recruiters definitely have a pattern in mind, and the more a candidate diverges, the more iffy their application becomes. Some of it is definitely luck, too.