Francisco Villegas' political allegiance was unmistakable as he disembarked from his flight into El Salvador. Draped in a flag adorned with President Nayib Bukele's image and clad in the light blue associated with the ruling party, Nuevas Ideas, he exuded confidence.

"We're going to win!" he exclaimed, greeted by cheers and applause from a small crowd awaiting their loved ones outside the arrivals lounge.

Like numerous Salvadorans residing abroad, Francisco is an unwavering supporter of El Salvador's controversial president, going so far as to travel from his home in Pennsylvania expressly to cast his vote for him.

"To be honest, in the past, I didn't pay much attention to who won," he remarked. "But over the past five years, I've witnessed significant changes and felt compelled to show my support by making the effort to come back. It's been a complete turnaround. I feel incredibly safe here now."

He's not alone in his sentiment.

In the lead-up to Sunday's election, Mr. Bukele's campaign advertisements have featured grieving relatives of victims of the country's major gangs, MS-13 and the 18th Street gang.

In emotional testimonials, they express gratitude to the president for his decisive military-led crackdown, which has transformed El Salvador from one of the world's most dangerous nations into one of Latin America's safest.

"Never again," reads the slogan.

It's a powerful message in a nation that has endured as much as El Salvador has. The implication - that voting for the president's opponents would pave the way for the gangs to regain power - is likely to secure Mr. Bukele's reelection by a substantial margin.

Recent polls show his main rivals collectively garnering barely 12% of the vote.

Armando Grande, a builder, used to faithfully support one of those rivals - the left-wing FMLN party. Yet, witnessing the transformation in the neighborhoods where he works, he now intends to vote for President Bukele.

"What we thought couldn't be achieved in decades, he's accomplished in five years. I can only rate his first term as a perfect ten," he declared.

The biggest and most glaring problem in the country was security.

"We were drowning," Armando remembers. Now the gang issue has been seemingly brought under control, he'd like to see the president focus on the Central American nation's urgent economic needs in his second term.

The government says its investments in Bitcoin - in which El Salvador declared the cryptocurrency legal tender - are now in the black.

But Armando readily admits President Bukele's Bitcoin experiment hasn't caught on with the general public or most businesses and would like to see him take more traditional steps to tackle the cost of living.

So it remains security - both the newfound sense of peace and the nagging fear that the bad old days might return - that will prompt most Bukele voters to the polls.

Critics, though, see a slide into authoritarianism and autocracy.

"To begin with, his re-election is unconstitutional", says Alejandro Diaz of the human rights NGO, Tutela Legal. Mr. Bukele says the constitutional court has ruled that he can stand for re-election as long as he doesn't exercise the role of president for six months before a second term.

Critics say he appointed loyalists to the court to reach a favorable ruling.

"One man's subjective decisions are going to dominate the three branches of power," Alejandro Diaz says of a second Bukele term.

"The control will intensify with no clear division between the powers of the state" he warns, saying that "through manipulation and propaganda, the majority seem to be comfortable with the erosion of their democracy in El Salvador".

Tutela Legal represents around 500 families who say their relatives have been unjustly swept up in the mass arrests as part of President Bukele's gang crackdown.

Some 75,000 people have been detained since the "state of exception" - an emergency measure granting draconian powers to the police and military - was imposed in March 2022.

Salvadoran and international human rights organizations claim many thousands of them have no discernible link to gang crime. Others were forced to collaborate with the gangs, either as lookouts or to hide guns or drugs for them, out of fear for their lives.

Bukele voter, Armando, has limited sympathy for such cases.

"It's impossible to avoid some innocent people getting caught up in it," he concedes. "But it's a necessary evil to fix this huge problem that we had."

That's not how Doña Berta Silvestre sees it.

She lives in Colonia Montelimar, a neighborhood that until recently was controlled by the fearsome MS-13. Her two daughters and her grandson were arrested for "unlawful association" leaving her to bring up four small granddaughters almost singlehandedly.

Berta insists her children were street vendors who were not involved in gang activity.

"I've had no contact with them in almost two years," she weeps. "I ask how they're doing but the authorities don't tell me anything." Berta is frantic with worry about their conditions and treatment inside jail.

She's been told it could be years before her daughters get a proper trial. Meanwhile, she fears what another five years of Nayib Bukele as president might mean for her beleaguered family.

"They say things are going to get even harder, especially for the relatives of those in prison," she sobs.

Outside the National Palace in San Salvador, workmen are erecting a stage and a huge sound system ahead of Nayib Bukele's planned victory party.

In just five years, this 42-year-old media-savvy leader has become a point of reference for conservative leaders across the Americas trying to burnish their credentials as "tough on crime".

From Argentina to the US, right-wing politicians have pointed to Bukele's model as the best way to tackle gangs.

He has undoubtedly changed the face of this impoverished, conflicted nation - and voters adore him for it. Rarely in Central America has a president been so clear of his rivals before a single vote was even cast.