Poland's president-elect Karol Nawrocki is taking up a largely ceremonial role, but his impact on the country's politics in the next five years may be profound.
Nawrocki's supporters, the national conservative Law and Justice (PiS) opposition, feel re-energised after losing power 18 months ago to Prime Minister Donald Tusk's pro-EU coalition.
They view his success in Sunday's vote – by a margin of 50.9% – 49.1% over liberal Warsaw mayor Rafal Trzaskowski – as the first step to a return to power.
Poland's president has limited influence on foreign and defence policy, but can propose and veto bills. Tusk's government lacks a big enough parliamentary majority to overturn a presidential veto.
The outgoing conservative president, Andrzej Duda, has used his blocking powers and the threat of using them to prevent the prime minister from delivering on many of his key campaign promises.
They include giving Polish women the right to a legal abortion up to the 12th week of pregnancy, legalising civil partnerships including same-sex relationships, accelerating onshore wind farm developments and removing political influence from the judiciary.
Nawrocki, a socially conservative 42-year-old historian, is widely expected to be an even tougher opponent for Tusk than Duda. Some believe the resulting paralysis could tempt the government to hold early elections before the scheduled autumn 2027 deadline.
"In all probability it will mean early elections, because he will veto any law the government passes," Konstanty Gebert, a journalist for weekly magazine Kultura Liberalna told the BBC.
"Constitutionally, early elections are difficult to do if the government doesn't want them, but if it is going from defeat to defeat and cannot govern, they might decide that they are the lesser evil," he explained.
Tusk's government has a parliamentary majority, so it can stay in office until autumn 2027 unless the coalition breaks up.
That union includes the conservative People's party, centrists and leftists, which is a key reason why Tusk has failed to reach an agreement on issues like abortion and civil partnerships.
Alternatively, the government could decide early elections are in its best interests.
