Workers in Guatemala City load a truck with voting materials for Sunday's election. (Luis Echeverria/Reuters)

As Guatemalans vote for a new president Sunday, their country faces a familiar litany of challenges — corruption, inequality, hunger and violence. All are driving a mass exodus to the United States: This Central American nation is the largest source of migrants apprehended at the border.

But during the three-month campaign leading to the vote here, any debate over platforms and policies has been overshadowed by legal battles to kick candidates off the ballot. Five of the 24 presidential hopefuls have been barred from running. The country’s highest court has nixed two of the top three contenders.

“There is a high level of confusion over who is in and who is not,” said Stephanie López, an analyst at the Central American Institute of Political Studies. “A significant percentage of the population has no idea who to vote for.”

Voters will cast ballots Sunday for a new president, members of congress and mayors. No presidential candidate is expected to garner the majority needed to win outright; a runoff vote between the top two is scheduled for Aug. 11.

The last time Guatemalans went to the polls, the president had just resigned and been arrested for alleged graft. The former television comedian Jimmy Morales, a political outsider running on an anti-corruption platform, swept into office.

Four years later, Morales is shutting down the United Nations-backed anti-corruption body that helped take down his predecessor after it began investigating finance irregularities in his own campaign.

Sandra Torres, the centrist National Unity of Hope candidate whom Morales defeated in 2015, is now the front-runner to succeed him. The former first lady — she was married to Álvaro Colom, president from 2008 to 2012 — has held a substantial and consistent lead in the polls. She also has the highest disapproval ratings.

Sandra Torres, presidential candidate of the National Unity of Hope party, greets supporters at a rally in Guatemala City. (Luis Echeverria/Reuters)

She and her party have a strong rural base of support. They have made aid and investment in health, education and agriculture cornerstones of their campaign.

Like Morales, Torres is named in a criminal case alleging campaign finance violations. But like the president and other officials, candidates have immunity from prosecution.

Carlos Barreda, head of the National Unity of Hope caucus in congress and part of the Torres campaign team, said the case against her has no merit.

“It is a case with political and spurious characteristics,” he said.

Torres is expected to finish among the top two candidates on Sunday. The question is whom she will face in the second round. Her two closest competitors were both kicked off the ballot.

Far-right Valor party candidate Zury Ríos has been barred under a constitutional ban that prevents coup leaders and their relatives from running for president. She is the daughter of Efraín Ríos Montt, who was charged with genocide in the massacres of indigenous Maya Ixil civilians during the country’s 36-year civil war.

Alejandro Giammattei, the candidate of the Vamos party, at a rally on the outskirts of Guatemala City. (Santiago Billy/AP)

Former attorney general Thelma Aldana, known for her work dismantling government corruption with the U.N.-backed International Commission Against Impunity in Guatemala, planned to run on an anti-corruption platform for the new Semilla Party.

In March, a judge issued a warrant for Aldana’s arrest for an alleged incident of graft related to a workshop contract. Courts ruled against Aldana’s candidacy, and she has not returned to Guatemala, saying her life would be at risk.

López said no presidential candidate has managed to fully capture Aldana’s or Ríos’s voters, and the electorate is not satisfied with the remaining candidates trailing Torres.

The closest contenders are Vamos candidate Alejandro Giammattei, a former penitentiary system director; PAN-Podemos candidate Roberto Arzú, son of former president Álvaro Arzú; and Humanist candidate Edmond Mulet, a lawyer and former diplomat.

“We are between three right-wing candidates,” López said. “All three have close ties to military circles.”

Several candidates say they would reduce migration by addressing conditions in Guatemala. More than 211,000 Guatemalans were apprehended at the U.S. border in the first eight months of the current fiscal year.

Barreda, the leader of Torres’s party, said they’re open to discussions with partners in the region about how to improve border security, especially to stop the smuggling of contraband.

“We do think U.S. collaboration is necessary,” he said.

He said Torres would address the causes of migration with public investment in infrastructure, health, education and small-scale agriculture in indigenous and impoverished rural areas, the source of much of the current exodus.

Giammattei would create an “economic wall” of jobs and opportunities to halt migration, he told the news agency EFE. He emphasized the need for greater foreign investment.

Arzú proposes U.S. military bases along the border with Mexico and U.S. assistance at points of entry and exit, customs and immigration.

Mulet says the key to reducing migration is creating jobs and economic opportunities for youth.

Indigenous social movement leader Thelma Cabrera of the new Movement for the Liberation of the Peoples has quickly risen in the polls to fifth place. The party’s platform for radical change has been gaining traction, but she is unlikely to make it to the runoff.

Thelma Cabrera, center, candidate of the Movement for the Liberation of the Peoples, arrives for a rally in downtown Guatemala City. (Santiago Billy/AP)

Throughout the campaign, candidates, officials and Morales have criticized election officials and the electoral process, laying the groundwork for questioning the results.

“They are fomenting the political climate of uncertainty and tension,” said José Carlos Sanabria Arias, sociopolitical unit director of Guatemala’s Association for Research and Social Studies.

Olivia Ajú is an indigenous street vendor in Guatemala City. She hopes a new government will improve conditions in the country but does not see many good options among the candidates. So many face proceedings to strip their immunity from prosecution for alleged corruption.

“The reality is that Guatemalans are undecided about who to vote for,” she said. “I think the majority of candidates running for office are doing so for personal gain. The people who really have the country’s interest at heart are very few.”