heavy heart, I voted for Komorowski,” Warsaw voter Alicja, 34, told AFP.
She had backed the anti-establishment candidate, rock star Pawel Kukiz, in the first round to protest the “lack of opportunity for young people on the job market” but Kukiz failed to qualify for the run-off.
Others are so disillusioned with politics they refused to vote.
“I voted for Komorowski five years ago, but I’m not voting at all this time. There’s no good candidate,” Marek Sadolski, a 46-year-old IT specialist, said on Sunday in the southern city of Krakow.
With the rivals running neck-and-neck in opinion polls, analysts insist the election is too close to call.
Analysts also suggest that Komorowski’s struggles are in large measure a signal from voters to the Civic Platform.
In power since 2007, the party has lost support over its failure to boost employment and keep its promises in key areas like administrative and tax reform.
The rival PiS, led by controversial ex-premier Jaroslaw Kaczynski, sees winning over disillusioned voters as key to making a comeback in both the presidency and parliament.
Kaczynski — whose twin brother, the late president Lech Kaczynski, died in a 2010 plane crash in Russia — makes no secret of his wish to return to power. A Duda win on Sunday could pave the way for a PiS general election win.
After his defeat to Komorowski in the 2010 presidential election, the 65-year-old Kaczynski floated Duda for president.
Komorowski and Duda were kissing babies and shaking hands nationwide right up to the last hours of the campaign, trying to woo the undecided.
Capturing the support of people who voted for Pawel Kukiz, the firebrand novice, in round one is key.
He finished a surprise third with 20 percent, backed especially by youth voters.
A country of 38 million people, Poland has avoided recession over the last quarter of a century.
The economy is set to expand by 3.5 percent this year, but joblessness is still high, standing at 11.3 percent in April.
“On Sunday, Poland will choose between two factions. First, that of reason and predictability represented by Komorowski, who is well-known to Poles,” Stanislaw Mocek, a political scientist at the Polish Academy of Sciences told AFP.
“And second, that of faith and unpredictability embodied by Duda, because this isn’t an independent politician: behind him lurks Jaroslaw Kaczynski.” Exit polls are expected at 2000 GMT when voting ends.