Billionaire former premier Andrej Babis and retired NATO general Petr Pavel topped the first round of the Czech presidential election on Saturday.
Babis scored 35 percent and Pavel 35.39, while economist Danuse Nerudova came third with 13.92 percent, according to results published by the Czech Statistical Office.
Babis and Pavel will face each other in a runoff in two weeks if the results hold, since no candidate achieved a majority of votes in the first round.
Turnout in the first round during the last presidential elections in 2018 was 62 percent.
A court in Prague acquitted Babis, 68, on Monday of fraud charges in a $2 million case involving European Union subsidies. The prosecution can still appeal. Babis had pleaded not guilty and repeatedly said the charges against him were politically motivated.
Despite a number of scandals, his popular support remains strong, particularly among older voters.
Zeman was the first president elected by popular vote. His second and final five-year term expires in March.
Lawmakers elected the previous two presidents, Vaclav Havel and Vaclav Klaus.
Websites of two presidential candidates hacked
The websites of two presidential candidates were hacked on Friday morning, according to the National Institute for Cyber Security.
Hackers blocked the web pages of General Petr Pavel, and academic Tomáš Zima. According to the institute, the attacks came from IP addresses across Europe and traces lead to the Russian hackers group known as NoName057.