Each State Guaranty Fund (which protects resident policyholders of an insolvent insurance company) sets a limit on the amount of protection provided, so it is important to review your state's coverage and to consider owning policies from more than one top-rated (as classified by A.M. Best) insurer, so that you do not have "all of your eggs in one basket." 

The chance of one top-rated insurance company becoming insolvent is quite low, but it can happen, and having your coverage spread between two or three companies provides better State Guaranty Fund protection, should one or more of your policy carriers become insolvent.