The main term voters associate with Mr. Fernández’s candidacy is “hope,” Mr. Giacobbe said.

Mr. Fernández, 60, a law professor who continued to teach as he campaigned for president, has projected an image of an ordinary man who takes pleasure in simple things like belting out rock classics while playing the guitar. Early on Election Day, he took his collie, Dylan — named after Bob Dylan — to a park where they played fetch.

Mr. Fernández has staked out more liberal positions than Mr. Macri on social issues. The most notable is Mr. Fernández’s support for decriminalizing abortion. He has a close relationship with his 24-year-old son, Estanislao, who is bisexual and has promoted his father’s candidacy during drag performances at venues in Buenos Aires.

On economic issues, Mr. Fernández is seen as more pragmatic than Mrs. Kirchner. She was criticized for distorting economic figures and building a patchwork of unsustainable subsidies that set the stage for the state’s insolvency when commodities prices dropped during her time in office.

Several voters said on Sunday that they felt they had no good options.

“I have a tiny hope that something could change,” said Noelia Mirta Tassone, 42, as she left a polling station in the Palermo district of Buenos Aires. But her overriding feeling as she cast a ballot was one of hopelessness, she said.

“This is a country that stumbles into a crisis every 10 years, regardless of who is in power, said Ms. Tassone, who voted for Mr. Macri in 2015 but now wants him out. “I know they are all thieves, and I’m fed up of standing by while they all steal from me.”

Mr. Fernández has been vague about his plans to stabilize an economy mired in a deep recession amid rising inflation and the steady depreciation of the local currency. But political analysts and ordinary Argentines expect that he will adopt more protectionist policies than Mr. Macri, who has championed a free market approach.