Yes, but if you keep going towards the CCAFS right before the gate you can park, and watch it. Just tell them you're there for the launch.
You'll want to get there early. Previously, they used to park people on the grass, no matter how many showed up. Now, they use one small parking lot, and when that fills up, they turn people away. For popular launches, this can be a problem. Depending on the launch and the time of day, Jetty Park, Playalinda Beach and the Cocoa Beach Pier are all good alternatives. I'm partial to Jetty Park, myself.
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