The Eurosceptic PiS party, which governed the country from 2015 until late last year, won 33.7 percent of the vote in elections to regional assemblies, according to the exit poll.
The ruling liberal Civic Coalition (KO) group came second with 31.9 percent of the vote in Sunday’s local elections.
The vote marked the first electoral test for the pro-European Civic Coalition since it came to power in the parliamentary elections of late 2023.
While PiS came in ahead of the KO, it was still well behind the combined score of the three groupings that make up the coalition government and appeared set to lose power in some regions, the Reuters news agency reported.
The centre-right Third Way group, a junior government coalition partner, finished third with 13.5 percent, according to the survey by pollster Ipsos.
The far-right opposition Confederation group was fourth, with 7.5 percent.
The Left party, another member of the governing coalition, came in fifth, gaining 6.8 percent.
The conservative opposition won the most seats in regional assemblies, but were outdistanced by the governing pro-EU bloc in mayoral races in several major cities, including Warsaw, Gdańsk and Katowice, the PAP news agency reported.
Mayoral races in several other cities, including the southern city of Kraków, were inconclusive and going into run-offs, according to the exit poll.
Rafał Trzaskowski, a senior liberal politician, won his second term as mayor of the Polish capital, securing over half the vote, public broadcaster Polish Radio reported.
Some pre-election surveys had suggested the battle for Warsaw would need to go to a second round. Trzaskowski won 58.9 percent, while his conservative rival Tobiasz Bocheński scored 18.5 percent, according to the exit survey.
Leftist candidate Małgorzata Bejat garnered 15.8 percent, the poll found.
Sunday’s ballot came ahead of European elections scheduled in Poland for June 9 and presidential elections next year.
Officials said turnout was around 51.5 percent, down from 54.9 percent in 2018.
More than 29 million Poles were entitled to cast their ballot in Sunday's local government vote, the PAP news agency reported.
The official election results are expected to be announced in the days ahead.
A second round of voting, where needed, will be held on April 21.
(gs)
Source: PAP