Bucharest voted Sunday in a mayoral election that could see Romania's capital become the first in the European Union to fall under far-right control, delivering a major blow to the country's pro-European ruling coalition.

The powerful post has stood vacant since May, when centrist Nicusor Dan left office midway through his second term after winning a presidential re-run. That vote was ordered after authorities annulled the previous presidential election over evidence of Russian interference that had propelled far-right candidate Calin Georgescu to an unexpected lead. Georgescu now faces trial on charges of attempting to undermine national security. Russia denies interference.

Polls close at 1900 GMT, with early results expected later in the evening. Surveys in recent days placed independent candidate Anca Alexandrescu – backed by the hard-right Alliance for the Union of Romanians (AUR) – neck-and-neck with Social Democrat Daniel Baluta. Centre-right contenders Ciprian Ciucu and Catalin Drula trailed further behind.

AUR has campaigned against military aid to Ukraine, criticised EU institutions and expressed sympathy for several of US President Donald Trump's policies on energy and migration.

A far-right victory in the capital would mark a symbolic breakthrough for AUR and intensify pressure on Prime Minister Ilie Bolojan's fragile coalition, which already faces a no-confidence vote this month over pension reforms and spending cuts.

The Social Democrats, a pivotal partner in the coalition, insisted on running their own candidate – a move that split the pro-European vote and boosted the chances of either Baluta or Alexandrescu.

Alexandrescu, a former Social Democrat spokeswoman and outspoken supporter of Georgescu, has appealed to voters disillusioned with established parties over corruption and poor governance.

Sunday's contest comes one year after the annulled presidential election triggered Romania's deepest political crisis in decades, exposing the country's vulnerability to foreign influence while shaking financial markets.