FILE PHOTO: People walk past the Supreme Court in Warsaw, Poland October 23, 2019. REUTERS/Kacper Pempel/File Photo

WARSAW (Reuters) - Poland’s Supreme Court on Tuesday rejected one of six requests for a vote recount by the ruling nationalists (PiS) following the Oct. 13 election in which they narrowly lost their majority in the upper house Senate.

The Law and Justice party’s setback in the Senate, coupled with a smaller than hoped for majority in the lower house, dealt a blow to its bid for a stronger mandate to pursue disputed overhauls of the judiciary, media and cultural institutions.

Supreme Court justices rebuffed the government’s bid for a recount in one Senate district, saying the difference between the candidates’ respective results was too small, and reserved a ruling on five other challenges.

PiS had said that it was demanding recounts because in some of the districts where it lost by a narrow margin there were a lot of ballots that were spoiled, not counted or left blank.

“The purpose of an electoral protest,” the court said in a statement, “is to point out specific violations of law affecting the outcome of the election...not to recalculate votes because of the slight difference between individual candidates.”

Opposition parties hold 48 of 100 seats in the upper house, but wield a majority thanks to three independent senators who are broadly supportive. The Senate has the power to delay legislation and appoint some prominent figures in the state.

Poland’s ruling eurosceptic nationalists have been embroiled in a long-running dispute with the European Union over its reforms of the judiciary and public media, which critics say have eroded the independence of both.