WARSAW, Poland — Conservative Karol Nawrocki’s victory in Poland’s weekend presidential runoff has set the country on a more nationalist course — and cast doubt on the viability of the centrist government of Prime Minister Donald Tusk after the defeat of his liberal ally.

Nawrocki, who was supported by U.S. President Donald Trump, won 50.89% of votes in a very tight race against Warsaw Mayor Rafał Trzaskowski, who received 49.11%, according to the final results published on Monday morning.

See Full Page