Venezuelan President Nicolas Maduro will seek his third term in office on Sunday in a vote that's regarded as the South American country's most open contest in more than a decade.

Analysts believe the presidential election could put Venezuela on a path to substantial change — on the proviso that Maduro is open to relinquishing power, if he is defeated at the ballot box.

Some public opinion polls have indicated a preference for opposition candidate and former diplomat Edmundo González Urrutia. The 74-year-old is widely regarded as the only contender capable of denying Maduro a third six-year term.

González was selected by the country's major opposition collation, the Democratic Unitary Platform, following the disqualifications of María Corina Machado and Corina Yoris.

Maduro's United Socialist Party of Venezuela (PSUV) has governed Venezuela since 2013, with the former union leader taking power after the death of his mentor Hugo Chavez. His 2018 election victory was widely regarded as an unfair contest, given that many prominent opposition parties were banned from taking part.

Maduro and his political allies have ramped up references to the prospect of post-election violence in recent weeks, sparking alarm within the international community.

"The destiny of Venezuela depends on our victory," Maduro said at a rally earlier this month, according to the Associated Press. "If we want to avoid a bloodbath, or a fratricidal civil war triggered by the fascists, then we must guarantee the biggest electoral victory ever."

The White House on Thursday expressed concern about the threat of violence in Venezuela's presidential election and urged Maduro to commit to a peaceful outcome, regardless of the result.

Asked in a press briefing whether Maduro was likely to rig Sunday's vote, John Kirby, White House national security spokesperson, said it was difficult to know how the situation would play out but that the U.S. wanted "to make it clear to Mr. Maduro that we're watching, we're watching closely."

Brazil's President Luiz Inácio Lula da Silva has also urged Maduro to respect the results, telling international news agencies that he was "scared" by the Venezuelan's recent remarks, Reuters reported.

Brazil's president added that Maduro "needs to learn that when you win, you stay; when you lose, you leave."

"On the basis of their own exit polls, the opposition will probably declare victory and push for regime change, ushering in a period of heightened political tension and uncertainty ahead of the inauguration," Andre Masuko, a research analyst with the Economist Intelligence Unit, told CNBC via email.

"However, we do not expect the Maduro regime to be overthrown. His strict control over the country's institutions, including the security forces, the judiciary and the electoral national council (CNE), will be instrumental in helping him to stay in power," he added.

Domestically, Masuko said that the EIU expects mass protests and increased episodes of violence to stoke social unrest and instability over the coming months.

"As a result, we are not ruling out the possibility that Mr Maduro could accept a defeat and subsequently allow for a transition of power, although this remains outside of our baseline forecast," he added.

Venezuela, which sits atop the world's largest proven oil reserves, has been gripped by a years-long political and socioeconomic crisis.

Venezuela's gross domestic product shrank by roughly three-quarters between 2014 and 2021, according to the Council of Foreign Relations, though the country's economy has expanded in recent years. In April, the International Monetary Fund said it expects Venezuela to register real GDP growth of 4% in 2024.

In the last decade, more than 7.7 million people are estimated to have left the country in search of better prospects, reflecting the largest exodus in Latin America's recent history and one of the biggest displacement crises in the world.

The United Nations refugee agency says that approximately 20% of the country's population has fled the country since 2014, citing rampant violence, gang warfare, soaring inflation, as well as shortages of food, medicine and essential services.

Maduro's government has sought to blame the U.S. and various international sanctions for the country's economic collapse, although analysts point out Venezuela's downward spiral started long before sanctions were imposed in 2019.

Eileen Gavin, principal analyst at risk intelligence company Verisk Maplecroft, said Venezuela's migrant crisis was "top of mind" ahead of the U.S. presidential election in November.

"There are strong reasons to want an end to the deep political polarisation and economic crisis in Venezuela, and a pragmatic solution to the sanctions situation," Gavin said via email.

"Biden administration's recent policy towards Venezuela – [centered] on renewed talks aimed the restoration of competitive politics, and a gradual dismantling of sanctions – corresponds to this 'pragmatic' agenda," she added.

"As such, we expect the current approach to continue – assuming there is no violence in the country. In similar vein, it is not in Maduro's interests to allow severe violence."