Can anyone? Yes, if you work for an approved media outlet. You have a good set of shots... put together a portfolio and start contacting newspapers, magazines, websites, etc. Long Beach is a difficult even to get credentials for, as many people want to shoot it (especially this year with the ALMS being there). It has lost a little of it's interest because it's no longer the season opener (as Las Vegas will be), but it still isn't easy.
If you don't get credentials this year... don't let it stop you from going and shooting from behind the fences again. Build-up a stronger portfolio and keep asking around. A suggestion... take more panning shots. People know you are shooting with fences in the way, and will understand that when they see a fence in the shot... but the key is showing you have the skills to get the shots (regardless of credentials). Right now all I see are high shutter speed shots. The shots from the parking garage at the fountain are nice (heck, you may have been the one standing next to me last year for a while), but you are missing the panning shots.
Keep at it... it takes time... but you can do it.
-Todd...