Paraguayans have elected Horacio Cartes, leader of the Colorado Party and one of the country's richest men, to the post left vacant by President Fernando Lugo's impeachment last year.
The millionaire businessman won a five-year term with 46 percent of the vote over 37 percent for Efrain Alegre of the ruling Liberal party, the Electoral Court announced after most votes were counted. Five other candidates trailed far behind.
Cartes, 56, had never voted before he joined the Colorado Party four years ago.
He pledged to reform his party, which was tainted by corruption during its 60-year reign until 2008.
"I'll need help from all the Paraguayans to govern in the next five years," Cartes said on Sunday night.
"Poverty, the lack of jobs for young people and international issues await us."
'Nothing more to say'
The UN estimates that more than half of Paraguayans live in poverty. Paraguay's census bureau puts the number at 39 percent in a country which is South America's third-biggest producer of soy, corn and sunflower seeds.
The president-elect owns controlling shares in banks, investment funds, agricultural estates, a soda maker and tobacco plantations.
Cartes is well-known in Paraguay as president of Libertad, the club that won last year's national football championship.
Alegre, 50, a lawyer and career politician, recognised his defeat despite saying earlier that he might challenge the outcome.
"The Paraguayan people have spoken. There's nothing more to say," he said in a brief concession speech.
Alegre's Liberal Party took over the presidency after withdrawing support for Lugo and clearing the way for his impeachment in June.
Congress removed Lugo, a leftist and former Roman Catholic bishop, after finding him guilty of mishandling a botched land eviction in which 17 police officers and peasant farmers were killed.
Some of Paraguay's neighbours compared the two-day trial to a coup and imposed diplomatic sanctions on the South American nation.
The leftist coalition that swept Lugo to power has since split, although the former president was again on the ballot, this time as a Senate candidate.
Lugo's administration was rocked by a sex scandal, after he admitted to having fathered two children out of wedlock while he was still a priest, and he faces at least two other as-yet unresolved paternity suits.
Many Paraguayans hope this election will encourage other countries to restore full relations.
Paraguay's serving president, Federico Franco, is barred by the constitution from running for re-election even though he is just serving out what remained of Lugo's five-year term. He will hand over the presidency in August.
Rivals have tried to link Cartes to drug running and money laundering, but he has never been charged with those crimes.
"The accusations made during this campaign have no truth to them, and personally I am very serene," Cartes said on Sunday.
Al Jazeera's Mariana Sanchez, reporting from Asuncion on Sunday, said many voters told her they were disillusioned by Lugo and wanted the Colorado Party to return to power.
"I talked to many people here who wanted change and since they were disillusioned by Lugo, they said change meant going back to the very conservative Colorado Party," she said.
Alegre had led corruption investigations in Congress, but his reputation as an honest administrator was undermined by an investigation into whether he misappropriated state funds while serving as Lugo's public works minister.
Paraguay's 3.5 million voters also cast ballots on Sunday for the country's legislature, 17 governors, local authorities and members of Congress.