With every step little Cristian Solano took, a flash of light interrupted the old sewer canal's damp darkness. At age three, Cristian was just little enough to be the only one walking among the group of Mexican emigres who crawled behind him. The shoes shone a light on the path to what they were sure would be a bright future in the United States of America.

I met Cristian, now 24, in Denver in early May, almost a year after a man named Donald Trump escalatored onto the Republican presidential primary stage with tirades against undocumented immigrants particularly from Mexico as well as obscure plans to build a 2000-mile (3219-kilometer) wall along the southern border.

The consensus is that neither the Great Wall of Trump nor rounding up and deporting the roughly 11 million undocumented immigrants - of which only about half are from Mexico - is practically or fiscally feasible. Deporting 11 million people alone, so the conservative projection goes, will cost taxpayers $400 billion (362 billion euros). And 72 percent of Americans actually favor a right to stay for the undocumented.

Stop talking, start listening

For the past year, Cristian has been serving as the president of student government at Metropolitan State University in Denver. He can talk openly about his lack of documents since he is protected by the executive order President Barack Obama announced in 2012, which offered temporary relief from the threat of deportation to young immigrants who came to the US illegally through no fault of their own.

"A lot of people are unaware of the fact that we are ineligible for public benefits," he says. "They think we are just here mooching off the system. They are unaware that the undocumented contribute an estimated $12 billion to social security, helping keep this program solvent, and fund health care and retirement for native-born people. They themselves are never going to see a penny of that money."

In February, the non-partisan Institute on Taxation and Economic Policy found that undocumented immigrants pay $11.6 billion in state and local taxes every year.

Paola Ontiveros and her family came to the US in 2001. Fleeing the violence that raged in their hometown of Ciudad Juarez right across the Mexican border, they overstayed their tourist visas.

Two years ago, Ontiveros became a US resident after marrying an American citizen. She works as an immigration paralegal for a non-profit organization in the Denver area, helping the - often undocumented - victims of domestic abuse or sex and labor traffickers.

Lowest level of illegal immigration in two decades

The elephant in the room is the fact Cristian and so many others came here illegally. It's the argument that Executive Director of Hispanic Republicans of Texas Trey Newton (albeit a little more graphically) makes.

"Donald Trump and Hillary Clinton would probably agree that we have a problem with undocumented immigrants living in the shadows in this country," the longtime Texas GOP operative says. "What do we do about it? You can't have a debate in Congress until the border is secured. When you have a patient who has been in a horrible car wreck and maybe has a cold, you don't treat the cold. You treat the bleeding artery first."

Just from October 2015 to February 2016, border officers detained 150,304 people at the Mexico-US border - an increase of 24 percent from the same window a year prior.

That sudden increase, advocates say, is actually happening because of Donald Trump.

The spike is particularly jarring since illegal immigration attempts overall have actually leveled off in recent years. In fact, they have fallen to the lowest level in at least two decades.

Members of Team Obama are quick to argue that's due to the deterring facts that his administration has pushed for instating the largest-ever force of border patrol officers. Additionally, Obama has actually deported more people than any other president - more than 400,000 a year as of late.

Obama in the crossfire

"Who is on our side?" asks Ricardo Rocha, a Denver-based Latino activist who was once an undocumented immigrant from Mexico himself. "Who is on my side in the Democratic Party, which systematically oppresses my people by deportation, breaking up families left and right?"

Ironically, Obama is also in the crossfire from the right for his executive tour de force in 2012 and 2014 when he used his presidential firepower to first offer relief to people who were brought to the US as children and later to undocumented parents of lawful US citizens (the latter has since been stopped by a split Supreme Court ruling). The president explained authorities would prioritize deporting those with a criminal background.

Waiting decades on visa decisions

As they try to navigate the immigration process, many new arrivals who are trying to take legal avenues get stuck in a convoluted systemic quagmire that leaves them with little choice but to disappear into the shadows.

Christine Alvarez is an undocumented mother of two. She didn't want us to use her real name, for fear of deportation. Too often it has been too close.

One of Christine's sisters is a US citizen. So, back in 2001, six years after she came here illegally, Christine filed the application for a family-sponsored visa. In 2008, seven years later, she heard back for the first time.

"We have received your application," was all the note said. Today, another eight years later, Christine is still awaiting a decision.

Right now, the government grants just 226,000 family-sponsored visas per year, for millions of applications - causing the excruciating backlogs. According to the Migration Policy Institute, as of April 2016, the US government was still processing some family-sponsored visa applications dating back to September 1992.

Make America White Again?

Gonzalo Ferrer, the national chairman of the Republican National Hispanic Assembly, says many undocumented immigrants have been in the country for multiple decades and are practically uprooted from their countries of origin.

He points to Ronald Reagan, the moral guidepost of the modern Republican Party, as someone who in 1986 signed a sweeping immigration overhaul into law - a move that included amnesty for almost three million undocumented immigrants.

What's different today? Ferrer believes it's the changing fabric of US society. The Pew Research Center found that in 1965, 84 percent of Americans were white. In 2015, that share had fallen to 62 percent. Ferrer's take on the Trumpwellian utopia: Make America White Again.

"We all know that if we were Irish, there wouldn't be an immigration issue in the United States," he says, but admits the problem goes farther than just plain racism.

"A lot of people don't like the rapid population change," he says. "When they go back to their high schools, they see a lot of people who make them feel as if their country has been invaded. Birth rates in the United States have come down. The kids who were supposed to be in schools are not there. Someone else's are."

The same Pew Research Center study also found that 49 percent of Americans want immigration to their country reduced, and 37 percent say immigrants are making American society worse in the long run. Those are the numbers that fuel Trump's ascent.

As he talks about such sentiments, exhaustion takes over Cristian Solano face. Although he was only three years old when he walked through that sewage tunnel, he remembers it too well. The tunnel - and his flashy shoes.

"We had to throw those shoes away to not be caught," he says. "That idealism of wanting to come here and thinking it would be so easy, thinking you just waltz in and have this amazing life - the shoes really symbolize that. Those lights remind me every day: I have to shine the light for everyone else."