Even if the venture, which has ambitious plans and many doubters, never gets off the ground, it poses an interesting, if, for now, mostly hypothetical question: what would compel someone to permanently give up life on Earth for extraterrestrial adventure?
For McLain, 30, a Maria Carrillo graduate, the motivation is advancing human society.
"My goal is to impact the world in as powerful and positive a way as I can," he said. "Going to Mars would be the most inspirational and positive thing I can do in my lifetime. I can't think of a more powerful way to help humanity grow than by helping humanity leave this planet."
Mars One, a Dutch company, hopes to put a settlement on the planet within a decade by tapping into human fascination with our closest neighbor. Part "Space Camp," part "Survivor," the company plans to raise money by staging an elaborate reality show and letting a worldwide audience help whittle down the applicants to 24 finalists through a series of challenges over the next two years.
The final two dozen will be trained as astronauts over the following eight years.
The company's website says it will need $6 billion to send a team of four to Mars.
"The next several selection phases in 2014 and 2015 will include rigorous simulations, many in team settings, with focus on testing the physical and emotional capabilities of our remaining candidates," Norbert Kraft, chief medical officer of Mars One, said in a statement. "We expect to begin understanding what is motivating our candidates to take this giant leap for humankind. This is where it really gets exciting for Mars One, our applicants and the communities they're a part of."
A Mars One spokesperson declined to answer questions and referred a reporter's inquiry to press releases published on the company's website.
The company has yet to secure a television deal for its reality show.
McLain, who is currently a musician and actor in Los Angeles, has approached the application process cautiously, and he is aware that many think Mars One's plans seem a bit far-fetched. But curiosity and a desire to leave his mark on humanity has led him to pursue this dream in the hopes that it does take off.
"Skeptically optimistic is the way I'm approaching this," he said. "Helping humans get off this planet is something I'd give my life for. I think there is a romanticism in being a pioneer. But I've kept my heart a little bit at bay. I will fall in love with this and devote my life to this and will be extremely disappointed if it doesn't happen."
McLain said he spent two days working on the application essay and video and paid a $20 application fee. The next step in the process is a comprehensive physical exam followed by a round of interviews.
"They are going to vet the crap out of us if we're going to Mars," he said. "Not just physically but mentally. I'm not going to lie, it's not going to be easy in any way."
According to Mars One, the company plans to launch a rover and supply capsules to Mars in 2020. The first four-person crew would lift off on a 210-day voyage to the planet in 2024.
The crew would live in the apartment-sized supply modules. They would get water by melting ice found under the planet's surface, and extract oxygen from the water.
The colonists would plant food in greenhouses. Every two years, another four pioneers would join them.
Mars One is not the only enterprise with plans to explore Mars. A venture called Inspiration Mars plans to send a married couple on a round-trip voyage to within 100 miles of the planet's surface in 2018.
Elon Musk, founder of SpaceX, the first private company to send a satellite into orbit, has said he wants to help establish a permanent human presence on Mars.
NASA has its own Mars ambitions. The U.S. space agency currently has three rovers on the planet exploring for signs of life. President Barack Obama has said he believes humans will go to Mars in the mid-2030s.
While Mars One claims to have advisors who have come from various space agencies, the organization has not partnered with NASA.
"NASA is not involved in Mars One," said Rachel Kraft, a NASA spokeswoman, offering no further comment.
Critics question Mars One's decision to prep average citizens for the mission instead of using well-trained astronauts and scientists.
"Colonies will need musicians, but you can't start a colony on Mars with musicians," said Chris Carberry, executive director of Explore Mars Inc., a group that advocates for Mars explorations. "You need really well-vetted, extremely talented people. They wouldn't have to be current astronauts, but they would need to be really well-trained as astronauts."
The organization's funding model and timeframe is also fodder for criticism.
"I just don't see it as viable in that timeframe," Carberry said. "They haven't raised remotely enough money needed to develop the infrastructure to colonize Mars."
McLain, who was on the reality show "The Sing-Off," said he was elated to learn that he was one of 1,058 worldwide and one of about 300 Americans advancing to the next round, but he isn't getting his hopes up yet.
"Just thinking about it makes me really happy," he said. "But I can't let myself get too emotionally attached. I haven't drunk the Kool-Aid yet. I'm testing the waters with my foot."
His parents and two younger brothers are supportive, but a little sad that he would consider leaving them forever, he said.
The Mars colonists would be able to communicate with loved ones on Earth but with a 20 minute delay, McLain said.
Among the personal items he would take on the voyage, McLain said he would pack some Shakespeare plays to perform in the new world, lots of music and a computer to produce music.
He would also bring plenty of photos of family and loved ones.
"I love my family fiercely, but I don't need to be near the people I love to love them," he said. "I could still communicate with them, but I wouldn't be able to touch them. And that would suck."
You can reach Staff Writer Matt Brown at 521-5206 or matt.brown@pressdemocrat.com.
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