Hungarian Prime Minister Viktor Orban's right-wing Fidesz party was facing a serious challenge in Sunday's nationwide local elections, as opposition parties fielded joint candidates in many cities.

More than 8 million people were eligible to vote for over 3,000 mayors and 17,200 local council members elected for a five-year term.

Fidesz has been dominant in local, national and European polls since 2010, but a unified opposition is posing a challenge to the ruling party.

Opinion polls show a tight race for the Budapest mayorship, with incumbent Mayor Istvan Tarlos of the Fidesz party practically neck and neck with opposition candidate Gabor Karacsony.

Read more: Merkel meets Orban in Hungary to commemorate 'Pan-European Picnic' 

Sex scandal

The release of a secret sex video of Fidesz's best-known mayor, Zsolt Borkai, has also dented the party's image. The video purportedly shows Borkai participating in an orgy on a yacht.

The conservative Fidesz, which casts itself as a defender of Christian and family values, and opposes the influx of refugees in the country, initially called it a "private matter," but the scandal has flustered the prime minister.

Read more: 'Orban cannot yield' on migration, Christian values, Fidesz official says

On Sunday, Budapest Mayor Tarlos urged Borkai to resign from his post, apparently concerned about the fallout from the scandal.

Borkai's actions were "insupportable, brazen, indefensible, vulgar and unworthy," Tarlos said on state radio. "The truth is that Borkai should resign, because it questions the achievements of others."

PM Orban said he would wait until Monday to declare his position on Borkai, who has also been criticized for his business connections and alleged corruption.

Read more: Hungarian civil society victimized by Orban government

shs/rc  (AP, dpa)

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