Madrid (CNN) -- Before Sunday's elections in Catalonia, Artur Mas, president of the region's parliament, promised a referendum on independence for one of Spain's most important regions if he won re-election. But after the election, Mas has a more difficult task because his center-right Convergence and Union coalition lost 12 of its 62 seats, a strong setback for a party that was hoping to gain a simple majority in the 135-seat legislative body. The Catalan Republican Left party was the big winner in the elections, winning 21 seats, according to the Catalonia elections web site, which reported 98% of the votes had been counted.
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Ruling party had hoped to win enough seats for simple majority
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Another party that supports independence makes big gains
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More than a million Catalans demonstrated for independence in September
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Catalans complain of cultural repression and economic slights dating to centuries
@placeholder has its own flag and language -- Catalan -- and various analysts say the economic crisis has brought long-simmering nationalist sentiment to the forefront.
@placeholder argues that it sends far more in taxes to Madrid than it gets back in central government spending, and that Catalan taxes help support poorer Spanish regions.
The regions administer key public services such as health and education, and in @placeholder's case, also the police and prisons.