Some guys have all the luck.

David Johnson was an obscure running back at Northern Iowa a year ago and is now the starter for one of the best teams in the NFL. His jersey went to the Hall of Fame after two games, and he's only the second player in history to score four rushing, four receiving and a kick return touchdown as a rookie.

This past Thursday night -- after Johnson logged a 19-carry, 92-yard performance in the Cardinals' 23-20 win over the Vikings -- the most famous player on the team playfully ribbed him.

"Somebody's got to ask David about that Christmas sweater," star receiver Larry Fitzgerald said with a devilish grin. "He had the date wrong on the ugly sweater party."

As Johnson realized his red, button-down sweater was the object of Fitzgerald's needling, he swung his head to the left.

"You like this?" Johnson said, smiling. "This is nice. It's that Express, man."

This is Johnson's present life: a key player on the field who is thriving off it. He turned 24 on Wednesday and proposed to his college sweetheart in June.

But it wasn't always this way. Johnson's story began much differently. His path to prominence had nothing to do with good fortune.

"Everybody's always surprised when he tells them," said Xavier Williams, a teammate in college and now with the Cardinals. "The way he acts is so nice, and he's always smiling and happy."

David Johnson was born in Memphis on Dec. 16, 1991, the fifth of six kids to single mother Regina Johnson, and he wasn't the only child she had that day. Older sister Danielle was born minutes before; younger sister Darnecia minutes after.

"Triplets," Johnson said.

At the time, Regina was already struggling to make ends meet for daughters Vatina and LaToria and son Marcus. Vatina, the oldest, was born with a mental condition which doesn't allow her to speak, read or write and caring for her took time and energy.

Regina was already spread thin, and suddenly, she had three more kids to care and provide for. She moved to Clinton, Iowa when David was 1 and worked whatever jobs she could find -- from a stint in a factory to shifts at Burger King, McDonald's and Long John Silvers.

"Literally every fast food," Johnson said.  "She bounced around from jobs. We bounced around from houses. We struggled just getting food daily."

Johnson saw the strain his mom was under and did as much as he could to contribute. As a kid, he would make money by detasseling corn, which consisted of walking through fields and removing the pollen-producing portion of corn plants to produce higher yields for the farmers.

He also made sure to get good grades and avoid bad situations.

"Me and my sisters, especially, being the babies, we tried not to worry her so much by staying out of trouble," Johnson said. "I played as many sports as I could just to keep myself busy so she didn't have to worry about a lot of things. It was very hard. It seemed like she was always tired and always stressed out."

The constant pressure took its toll, and Johnson said Regina turned to drugs and alcohol to cope. The family's low point came when the triplets were in fourth grade and Regina was jailed on an alcohol-related offense.

Dirt poor and without a dad from the start, the young Johnson trio moved in with LaToria as their mom was placed behind bars for multiple weeks.

"That's when it felt like life was almost too much for us," said Johnson, eyes welling at the memory.

After Regina was released from jail, she moved into a halfway house with David, Danielle and Darnecia. The triplets tried to keep some semblance of a normal childhood as they started fifth grade. Regina worked to treat her alcohol abuse.

Between the wakeup call from the jail stint and the halfway house supervision, Regina found the guidance she needed.

"I'm glad we ended up going there at the end of the day because she ended up getting clean," said Johnson, who asked that his family not be interviewed for this story. "Now she doesn't do anything at all. She ended up going to church all the time, becoming a Christian. She ended up helping me become a Christian. That was one of our lowest moments, and I'm glad it happened."

As Johnson grew older and home life stabilized, his athletic exploits shined. He became a standout in football, basketball and track at Clinton High School and started garnering college interest on the gridiron. Johnson's lack of a clear position may have cost scholarship offers from the biggest schools, so he accepted an opportunity to play for Northern Iowa.

Johnson was recruited as a wide receiver, but soon grew so big that it made more sense to put him at running back. Over the next four years, Williams, a nose tackle, became close with a teammate who wasn't going to let his opportunity slip.

"David is the personification of what happens when you're a great athlete and you truly work at it," Williams said. "His game has evolved a lot from when he was a freshman in college. Every year you could see he got bigger – way bigger – but he got better in everything he did.

"I would be working out in the weight room with him, and he'd be doing crazy amounts of weight. I'm sitting there looking at him like, 'Chill out, man.' That was David. Always working out, always running. Coaches would tell him, 'Hey, you should work on this,' and he'd hit it full speed."

Johnson broke 15 school records his senior year at Northern Iowa and was drafted by the Cardinals in the third round in May. Some panicked when the team's top two running backs, Chris Johnson and Andre Ellington, went down with injuries in Week 12, but Johnson has stepped in seamlessly the past two games.

Cardinals coach Bruce Arians calls him "a mature young man." Quarterback Carson Palmer said Johnson has improved as his responsibilities have grown.

"It's not easy for a rookie, but he's earned our respect and our trust, everybody in that room," Palmer said.

Regina has been to three Cardinals games this season, and David loves seeing the look on her face in the crowd. For a woman who spent the majority of her time working or parenting, sports as entertainment is a novel concept.              

"The football, the games, it was something she was not used to," Johnson said. "You could tell when I was in high school when she first went to games, she was kind of out of her element so she didn't talk as much. Now she's a little bit more talkative, knowing more about football. … It's really cool to see her. Her eyes widen up. Her eyes glow."

Regina and several other family members made the trip to St. Louis in Week 13 for David's first career start. They stopped at the team hotel on Saturday night for a few moments with him in between Johnson's game preparation.

Every reunion is a reminder of how far the family has come. For Johnson and countless other NFL players, a challenging upbringing is constant motivation.

"A lot of people here are running from the past," Williams said. "They understand what the other side of the fence looks like. Even when you're young, you may not fully know what's going on, but you know 'I don't want to go back to that.' You have an opportunity like this to really change your life, and people say it all the time – this can change generations of your family. If you have an opportunity like this, you've got to take full advantage of it."

By all accounts, Johnson is doing that. He's drawn rave reviews for the progress he's made in picking up a complicated offensive scheme. Through 13 games, he has carried the ball 76 times for 330 yards, a 4.3 yards-per-carry average, and added 26 catches for 293 yards.

"You usually don't have that versatility," said Eagles coach Chip Kelly, this week's opponent. "Usually you have a big back that's kind of a banger, but he can't be (only) a third-down back. I think David is a three-down back and has been very impressive."

As the praise mounts for Johnson, he circles it back to his mom. She grew up poor in Memphis and raised six kids by herself in Iowa. Regina had her battles, but persevered to give David and his siblings a chance to break the cycle. After all that, they deserve a slice of the good life.

"Without her, I wouldn't be here," Johnson said. "She could have easily had us go to foster care or had us adopted. By the time she had triplets she was probably overwhelmed, and she never gave up. I'm very proud that I'm able to make her happy."