BARCELONA ? The wealthy, semiautonomous Catalonia region around Barcelona gained sweeping new powers Sunday to run its own affairs, according to preliminary results of a historic referendum that some fear could leave Spain’s government cash-strapped and powerless.

With nearly 45 percent of the votes counted, 74 percent of voters approved the blueprint and just under 21 percent rejected it, the Catalan government said.

Turnout was about 48 percent.

The region considers itself a nation within a nation. At stake in the referendum are a bigger slice of tax revenues collected in Catalonia, a say in the appointment of judges and prosecutors to courts run from Madrid and an indirect proclamation of Catalonia as a “nation.”