Prime Minister Viktor Orban's Fidesz party is expected to maintain its dominance in nationwide municipal elections, with the far-right Jobbik party seen making gains in rural areas.

Pollster firm Ipsos predicts Sunday's voting will "essentially result in victory for Fidesz," whose candidates are tabbed to win the mayor's office in nearly all of Hungary's 23 largest cities, as well as in Budapest, the capital.

Jobbik, trying to distance itself from earlier anti-Roma and racist statements, may edge out the fragmented Socialist Party in most county assemblies and could elect mayors in a handful of cities with populations over 10,000.

Orban won re-election in April when Fidesz secured a new two-thirds parliamentary majority. A July speech expressing his desire to turn Hungary into an "illiberal state" sparked international criticism.