Bratislava/Prague - Slovaks are voting for their new head of state on Saturday, in an election that is likely to turn into a duel between the centre-left government and the right-wing opposition.

The race is led by incumbent President Ivan Gasparovic, 67, who is supported by the very popular prime minister, Robert Fico. Gasparovic's campaign has made heavy use of the association during the race.

Fico voiced his support for the incumbent as polls opened.

"Presidents are picked by citizens. I would be glad if they chose President Gasparovic," he told reporters, calling for leadership continuity amid the economic crisis.

Campaigning has been banned in Slovakia since Thursday morning. But Fico made the remarks while visiting the neighbouring Czech Republic.

Polls showed that Gasparovic faced a challenge from the joint opposition candidate, lawmaker Iveta Radicova, 52. She is the only one of the six remaining contenders who stands a chance of defeating the incumbent.

Analysts, who consider a clear victory in the first round highly unlikely, expect her to make it to a run-off planned for April 4.

To win in the first round, a candidate would have to receive votes from more than a half of 4 million eligible voters.

Analysts expect less than a half of voters to cast a ballot on Saturday. Central Election Committee official Livia Skultetyova described the turnout as "decent", the CTK news agency reported.

"It certainly won't be decided now. There will be a second round," 44-year-old entrepreneur Vladimir Santur, said echoing analysts' opinion. He gave his vote to Radicova.

The president, who faces criticism for what analysts call a dull performance during his five years in office, campaigned on nationalist and welfare issues, where he is aligned with Fico.

A former law lecturer, Gasparovic is seen as an accidental head of state, who was elected after unexpectedly proceeding to the presidential run-off in 2004.

Voters chose him as the lesser evil in a race against former premier Vladimir Meciar, a highly-divisive authoritarian politician whose undemocratic and anti-Western politics brought the Central European country of 5.4 million into isolation in
1990s.

Gasparovic, a parliament speaker between 1994-1998, had been Meciar's close ally. But the two politicians fell out in 2002.

Radicova, a sociology professor who served a brief stint as a labour minister under the previous centre-right government, would be Slovakia's first female president if elected.

She is cashing in on entering politics only three years ago. "She has been in politics for only a few years. She is not so spoiled," Santur said.

Representing Slovakia's aspirations of a dynamic and cosmopolitan culture, she ran an Obama-like campaign, backed by celebrities, academics and athletes, such as tennis player Dominika Cibulkova.

But she is a deputy of the opposition Slovak Democratic and Christian Union, which is unpopular for introducing belt-tightening pro-market reforms that kick-started the troubled Slovak economy by luring in foreign investment.

In addition, her liberal views on abortion earned her harsh criticism from the Roman Catholic Church, the main faith in Slovakia.

Polling stations close at 10 pm (2100 GMT). First results should be available early Sunday. (dpa)