The leading candidate, according to a Jan. 31 El Mundo CR-OPol poll, is the conservative Fabricio Alvarado from the Evangelical National Restoration party.
Alvarado, with 26 percent, began to inch ahead of his competitors when “religious shock” spread among the public following the Inter-American Human Rights Court's insistence that gay marriage be legalized.
Born in San Jose, Costa Rica, the 43-year-old is running on a fundamentalist religious platform: he wants to "defend life and family" and "improve sex education in schools… to prevent teenage pregnancy."
He's also campaigning on four other agenda items: zero coalitions or political liabilities to other factions; an end to government corruption; economic austerity, and teleworking to promote efficiency.
In second place, with just over 20 percent, is a candidate from the once-powerful center-right National Liberation Party (PLN).
Antonio Alvarez Desanti's platform includes generating 150,000 jobs and deploying a "heavy hand" against crime, including putting more police on the streets.
He says he'll create a modern public transportation system, an "efficient" public sector, and improve the national economy. He's promising more financial credit to farmers if he's elected.
Branded an "opportunist" by his own party, Desanti hopes to unite the PLN, which has splintered as members scramble to regain the power they enjoyed in the past.
Desanti has also vowed to eliminate corruption, rampant within his own party: in the 'cementazo' scandal, a loan of US$30 million allegedly given to a politically connected cement entrepreneur is currently unaccounted for.
The candidate himself has been accused of corruption, namely buying Indigenous territory in Panama. And he's been formally accused of trying to interfere in an investigation into his own company for violating labor laws.
Carlos Alvarado has climbed to 18 percent, up from 6 percent just a few weeks ago. Having never served as an elected official, he's hoping that coming from the ruling Citizens' Action Party will earn him credibility among voters.
Like Castro and Desanti, Alvarado has both corporate and government experience: he served as minister for the Department of Development and Social Inclusion and the Department of Labor under the current government.
With crime soaring in Costa Rica, Alvarado is promising to control delinquency and the sale and use of guns. He's also pushing for government transparency.
Setting Alvarado apart is his commitment to the environment: something the current administration promoted, but hasn't been able to pull off. He wants to pass a new water law to ensure that everyone has equal access. He also wants Costa Rica to start using one of its main assets – the sun – to generate energy.
Another stand-out position is that Alvarado wants to make governing more inclusive: he supports gay marriage and Costa Ricans' right to officially change gender.
Juan Diego Castro, from the National Integration Party, was leading the polls earlier this month, but has since slipped to fourth. Projections suggest he'll take about 13 percent of the ballots.
Castro, a conservative lawyer and former minister of public safety in the 1990s, is running on a mainly anti-corruption platform. Also on his agenda is streamlining government projects and agencies, including the police, and limiting functionaries' international travel.
The 62-year-old, who wants to bolster small and medium-sized businesses, regularly sounds off on social media, earning him comparisons to U.S. President Donald Trump. Responding to criticism in La Nacion, Castro posted: "They are crazy... The psychopaths of the newspaper La Nacion... You are reaching unimaginable extremes of madness. Do they think that this country relies on that newspaper? They are begging people to buy that printed lampoon. They will soon disappear."
Castro once claimed on Facebook that a former female co-worker in the judicial system gave oral sex to the Supreme Court president in exchange for a promotion – a claim the woman has denied. And he has called environmental organizations "eco-terrorists" and said he wants to bring back mining.
Rodolfo Piza, from the Social Christian Unity Party, has about 12 percent of votes. His main talking points include combating corruption, improving public transport, boosting the economy and creating 300,000 jobs to tackle the 9 percent unemployment rate.
The self-described academic, lawyer and public leader also supports gay marriage. If elected, Piza says he'll propose a civil union law "that guarantees against discrimination of same-sex couples."