Zeman, the leftist premier in 1998-02, leads the polls with about 25 percent support. Fischer, a centrist and a former state bureaucrat, gained significant popularity when he led a caretaker government in 2009-10. He polls at about 20 percent.
As the campaign approached its end on Tuesday, eight candidates were busy on the stump. The ninth — Franz — had other matters to deal with: a final rehearsal of his opera "War with the Newts" at the State Opera.
Torn between art and politics, Franz cut short his appearance at an election debate to return to the opera house that is part of Prague's National Theater.
But he committed to staying to the end of Thursday's final televised debate. It wasn't an easy choice, but he realized his credibility demanded that he take part.
"For a Czech composer to have a world premiere in the National Theater is something extraordinary. I had to make a choice between a service to the public and the fulfillment of my life-long dream. I've made the choice and will be at the debate."
Associated Press video journalist Adam Pemble in Prague contributed to this report.
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