Political parties are wrapping up campaigns for elections in Spain's Basque and Galicia regions that offer a slim chance of ending the nine-month deadlock at national level and avoiding a third general election in a year.

Acting Prime Minister Mariano Rajoy's conservative Popular Party has been running a caretaker government in Madrid following inconclusive national elections in December and in June. The party won the most seats in both but lacks the votes in Parliament to win a confidence vote to form a new government.

But now it hopes a strong showing in Galicia and the possibility of a post-election deal with the ruling Basque Nationalist Party will strengthen its hand at national level.

Campaigning for both elections ends at midnight Friday with the elections to be held Sunday.