The only shot you have is to be a guest of Microsoft.

http://majornelson.com/2015/05/14/xbox-at-e3-2015/

Xbox FanFest: E3 2015

Xbox will give 500 lucky fans a one-of-a-kind ticket for E3 week, the gaming industry’s biggest showcase. The Xbox FanFest Ticket will include:
Entry into the Xbox E3 2015 Briefing on Monday, June 15th, 9:30 am PT, at the Galen Center in downtown Los Angeles.
Invite to the exclusive Xbox FanFest Party, Monday afternoon, June 15th, where fans will get to play the best exclusives and biggest blockbuster games this holiday and beyond.
VIP access to the Xbox esports Celebrity Challenge & Twitch Party sponsored by Xbox.
Meet-and-greet with some of the industry’s top developers, leaders and influencers.
Even more surprise events during the week.

Be in the gaming industry or game industry journalist.

I'm actually going to try this. wish me luck, If i get in I will create a nice thread for everyone to check out.

I have a friend who used to work in Bamco and he used to go every year. He lorded it over me every time he went. I'd be mad but he was really cool.

Wait, what! Being a member of VGChartz isn't enough ... someone remind me why the hell I signed up then!

Its not open to the general public,

https://www.youtube.com/watch?v=6rKg11tu3HA

as this video makes it all clear.

Gone are the days when gamers could go to E3...

E3 used to be open to the public? 

As far as I'm aware, yes.

So you just be one of the first 500 people to show up and get a ticket? No entering into a drawing and stuff? That sounds good.