Can you insure a car in a different state if it is registered in the car owner's state?

Yes What we're trying to do is have my boyfriend drive my NJ car to California and I will fly out later on (about 2 months). In the meantime, the car is in my name, I pay the payments on it, and it is insured with a NJ-based insurance company. I did not contact my insurance agent to let him know I was doing this yet, just thought that insurance covers a car, not a person. But recently I found out maybe I'm wrong. So now, we're trying to get the car insured but my boyfriend's insurer, State Farm doesn't cover NJ-registered cars. What can we do now?