That argument may not work since all they'll say is that California is not only the 9th largest economy in the world (were it an independent country), but that it has the highest GDP of any state in the US. Latest figures have California at number 1 with US$1.94 Trillion and 13.3% of national GDP (no 2 is Texas with US$1.31 Trillion and 7.95%, no 3 is New York with US$1.16 Trillion and 7.68%, no 4 Florida at US$754 Billion and 5.2%, and Illinois wraps up no 5 with US$644 Billion and 4.4% of national GDP).
California's economy, good and bad, is one of the reasons they look down on much of the country - in particular what the West and East Coasts refer to as flyover country.
Here is the Democrat’s take on Illinois. Even they realize it is bankrupt. CA, and NY are not far behind. This will not end well.
http://www.statebudgetcrisis.org/wpcms/wp-content/images/2012-10-12-Illinois-Report-Final-2.pdf