Czechs voted on Friday in day one of presidential polls with a billionaire, a general and an academic leading in the first of a likely two-round vote seen as too close to call.
The winner will replace Milos Zeman, an outspoken political veteran, following a period marked by the country's 2022 EU presidency as the war in Ukraine raged.
The victor will face record inflation in the central European country of 10.5 million people, as well as bulging public finance deficits related to the war in Ukraine.
Unless a candidate wins more than 50 percent in the two-day first round, which is considered unlikely, the two top-placed contenders will go head-to-head in a second round on January 27-28.
"If you asked me to place a bet (on the result), I wouldn't," Metropolitan University Prague political scientist Petr Just told AFP.
Populist ex-prime minister Andrej Babis, retired general Petr Pavel and university professor Danuse Nerudova are vying to become only the fourth president since the Czech Republic was founded in 1993 following the collapse of the Soviet Union.
Casting his ballot at a school in Prague, voter Ivan Andrys said the next president should be impartial and act in lockstep with the government on foreign policy, something Zeman often failed to do.
"Of course, he or she must not give (in) to pressures... whether political or economic," Andrys said.
"I think the president should be able to unite people, be inspiring, responsible and attentive to the needs of every individual citizen," said Alena Migdauova, who voted at the same school-based polling station.
Business tycoon and former prime minister Babis, 68, is the fifth wealthiest person in the Czech Republic, according to Forbes magazine.
Pavel, 61, is a former paratrooper who was decorated as a hero of the Serbo-Croatian war during which he helped to free French troops from a war zone.
He went on to be the chief of the Czech general staff and chair of NATO's military committee.
Nerudova, the youngest frontrunner at 44, has a strong focus on social issues and is counting largely on the backing of younger voters.
- Six wines, three shots -
Voting in his home village of Cernoucek north of Prague, Pavel said the main goal was to restore dignity of the presidential office after the divisive Zeman's 10 years in office.
"We should also establish normal communication and try to achieve results not through confrontation but by cooperation," he added.
Babis, voting in Pruhonice just south of Prague, said he was counting on his political experience to carry him to victory.
"I know most presidents. And my advantage is that I know what all ministries are dealing with," he added.
Polls suggest that both Pavel and Nerudova would beat Babis if they face him in the second round.
Five candidates -- two senators, a far-right lawmaker, a former university rector and an entrepreneur -- trail behind the top three favourites.
The Czech president's role is largely ceremonial, but the head of state names the government, picks the governor of the central bank and constitutional judges, and serves as top commander of the armed forces.
But Zeman, a controversial politician who once confessed to a daily diet of six glasses of wine and three shots of spirits, repeatedly exploited loopholes in the constitution to increase his influence.
Polling stations opened in the first round at 2:00 pm (1300 GMT) and will close at 10:00 pm. They then reopen from 8:00 am to 2:00 pm on Saturday.
The first-round results are expected on Saturday evening.