Costa Ricans on Sunday voted in conservative populist Laura Fernandez to lead the country as president, who is likely to continue an aggressive reorienting of domestic politics started by predecessor, President Rodrigo Chaves.

Preliminary and partial results showed the Costa Rican president’s handpicked successor captured the win with a resounding first-round victory, eliminating the need for a runoff in a crowded field after Sunday's election.

The Supreme Electoral Tribunal reported that with votes from 93.7% of polling places tallied, Fernandez of the Sovereign People's Party had 48.3% of the vote. Her closest challenger was economist Alvaro Ramos of the National Liberation Party with 33.4%.

Ramos conceded Sunday night and pledged to lead a "constructive opposition," but one that would not let those in power get away with anything. Fernandez will not be formally declared the winner until electoral officials complete a manual count scheduled to begin Tuesday.

"In democracy, dissent is allowed, criticism is allowed," he said.

Fernandez spoke to her supporters after Ramos conceded Sunday night and President Rodrigo Chaves congratulated her.

"Costa Rica has voted and it has voted to continue the change, a change that only seeks to rescue and perfect our democratic institutions and return them to you, to the sovereign people, to create more well-being and prosperity for our people,” Fernandez said.

"The mandate the sovereign people give me is clear: the change will be deep and irreversible,” she said. Fernandez was scheduled to give a news conference Monday.

At least 40% of the total vote is required to win the presidential election in the first round. Otherwise, the top two candidates will go to a runoff on April 5.

Fernandez campaigned on continuing the policies of the term-limited Chaves.