BARCELONA - Catalans go to the polls on Sunday in a regional vote which offers the choice of an exiled separatist politician who led a breakaway push in 2017, or an anti-independence government led by the Socialist Party.

Opinion polls forecast a comfortable lead for Socialist candidate Salvador Illa over the separatist Junts and its rival Esquerra Republicana de Catalunya (ERC), which currently governs the wealthy northeastern region.

Junts' candidate is Carles Puigdemont, who was Catalonia's president during an ill-fated attempt to wrest the region from Spain in 2017 before fleeing to Belgium, and he has vowed to resurrect an independence bid

Junts' candidate is Carles Puigdemont, who was Catalonia's president during an ill-fated attempt to wrest the region from Spain in 2017 before fleeing to Belgium, and he has vowed to resurrect an independence bid.

"Today we are stronger, more resilient and determined. The time to return has come," Puigdemont told a closing campaign rally in southern France, near the Catalonia border, on Friday.

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Puigdemont faces prosecution in Spain over the failed independence bid, which triggered the country's worst political crisis in decades. He is set to return home following an amnesty put forward by the Socialist national government that would annul the arrest warrant he faces.

"We are the largest nation in Europe that is not a state and (Spain) has not been able to stop us from working without rest to achieve independence," said Puigdemont.

The Socialists stand to win 40 seats in the Catalan assembly, with Junts forecast to get 34 and ERC 26, according to a poll of polls by El Pais newspaper.

A government led by Prime Minister Pedro Sanchez's Socialists in Catalonia would end a decade of separatist governments that have roiled Spanish politics, and would be a vindication of Sanchez's conciliatory approach with Catalonia.

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"We need a change on May 12 and only Salvador Illa can lead it," Sanchez told the Socialists' closing rally in Barcelona, arguing that only Illa can give stability and improve the social climate in the region.

It is uncertain what the impact will be of Sanchez's surprising five-day break from office last month to weigh his possible resignation over what he said was a smear campaign directed against his family by right wing opponents.

His break "has mobilized a lot the Socialist vote" in Catalonia, said a Socialist source.

Some surveys show that around 40 percent of voters are undecided, so any outcome is possible.