Urban voters, women and ethnic minorities overwhelmingly supported Dan. His conservative rival, George Simion, has announced plans to file a legal challenge to annul the election, citing 'foreign interference.

Elon Musk and David Sacks, both White House advisers, weighed in separately on the election in Eastern Europe.

Defeating populists never signals an easy return to the status quo ante.

BUCHAREST, Romania — The pro-European Union candidate in Romania’s tense presidential runoff has taken a lead in the polls, preliminary electoral data shows, in a closely watched vote against a hard-right nationalist that could determine the geopolitical direction of the NATO member country.

High voter turnout, especially among young people and women, helped Bucharest Mayor Nicușor Dan win Romania's presidential runoff, defeating the hard-right George Simion. View on euronews

Romania’s assets staged a relief rally after a centrist candidate defeated his nationalist opponent in the presidential election, with investor focus now shifting to how quickly a new government can fix the state’s finances.

Nicușor Dan swept to victory in Romania's presidential election on Sunday, defeating far-right nationalist rival George Simion with nearly 54 percent of the vote. Dan, 55 the centrist mayor of Bucharest and former mathematician who campaigned for an "honest" Romania,