BRATISLAVA (Reuters) - Fifteen candidates including an experienced diplomat backed by the ruling party and a political newcomer promising to fight corruption announced bids to become Slovakia’s president by Thursday’s deadline.

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Voters’ concerns over rule of law and the state of democracy one year after the murder of a young investigative journalist are expected to play a part in the two-round election, scheduled for March 16 and 30.

Mass protests against political sleaze forced prime minister Robert Fico to quit after a decade, but his leftist Smer party remains in power.

Most of the leading candidates are pro-EU, making Slovakia unlikely to join the rising tide of euroscepticism sweeping the European Union.

The president does not wield much day-to-day power but is a key player when new governments are formed and appoints judges to the constitutional court.

The incumbent, Andrej Kiska, who is unaffiliated with any party and sided with protesters calling for Fico to step down last year, is not seeking re-election.

The race has no clear front runner yet. A survey this month by the pollster Focus had career diplomat and European Commission Vice-President Maros Sefcovic tied with scientist and entrepreneur Robert Mistrik at 16.5 percent.

Sefcovic is backed by the ruling party, which continues to lead surveys despite losing some support after the murder of Jan Kuciak and his fiancee. Mistrik has the backing of the main opposition party, the liberal Freedom and Solidarity (SaS).

Both men are 52 years old and promise to support Slovakia’s status as a member of the EU and euro zone.

Their closest rival, 61-year-old supreme court judge Stefan Harabin, describes himself as a Christian patriot. He wants to scrap EU sanctions against Russia and calls Kiska a traitor controlled by foreign powers.

Marian Kotleba, leader of the far-right People’s Party-Our Slovakia, which won seats in parliament for the first time in 2016, has support of around 8 percent.

If no candidate scores 50 percent in the first round, the top two candidates go into the runoff.

Opinion polls on voters’ second choices suggest that both Sefcovic and Mistrik would beat either of the anti-establishment candidates in the second round.