Long before Ted Cruz became a senator from Texas, he was a gamer. He’s known for being pugilistic on the Senate floor, but sometimes he’d rather be fighting cartoon zombies on his iPhone.

It’s an uncommon lens through which to view Cruz, a controversial conservative figure who is now running for the highest political office in the country. Cruz’s video game habit fits into a largely hidden geek persona that lurks just behind his better-known public reputation as an obstinate Tea Party firebrand.

At the moment, Cruz is playing “Plants vs. Zombies,” a game where users collect sunlight points to feed plants who fight off waves of zombies; “Candy Crush,” the puzzle game where he claims he’s in the 217th level; and “The Creeps!,” a tower defense game.

His video game addiction is so severe, Cruz says, he has to proactively deny himself the ability to spend time on it.

“I don’t have a console, mostly as a time management tool, because if I had one, I would use it far too much,” he told The Daily Beast.

The Texas Republican explains the origins of his love for video games as a generational phenomenon. He ticks off his favorite games at his childhood arcade: “Galaga,” “Space Invaders,” “Centipede.”

“I was a kid growing up in the ’70s and ’80s. I had a Nintendo, an Atari,” he said. “I still remember the Christmas we got our first ‘Pong’ game.”

His love for video games evolved over time as he entered college, then law school. David Panton, who was Cruz’s roommate for 4½ years through Princeton and later Harvard Law, recalls all-nighters spent on “Super Mario Brothers” and Japanese fighting games.

Putting aside debate and school government, Panton said, “our favorite activity…was video games.”

“We would spend many hours playing video games, often until the sun came up. In reality, Ted was a much better player than I was—he beat me in everything—but I think I was sufficiently competitive that he felt somewhat challenged,” Panton told The Daily Beast. “I’m a far better video game player today as a result of Ted Cruz.”

Video games have only once entered into Cruz’s comments about government and public policy: in December, when he publicly mused about the overuse of drones in warfare.

“There are also concerns from the perspective of national security. No administration has used drones as aggressively as has the Obama administration. And I’m worried about what I would call video-game warfare,” Cruz said at a Foreign Policy Initiative forum in Washington, D.C.

Here’s where video games help: Cruz suffers from a perception of rigidity. When asked a question, his responses are always airtight and measured, the mark of a former debate champion. Often these conversations seem stilted and rehearsed. Unlike a more gregarious politician like Senator John McCain, Cruz doesn’t make unscripted jokes or pal around much.

If asked a question Wednesday that he was previously asked on Monday, he will repeat his original answer nearly word for word, as if it were memorized, raising the risk of questions about how genuine he really is.

His passion for video games, and the way he uses them to connect with his children, cuts through some of that.

“I play with my daughters,” he told The Daily Beast. “One of the fun things that I do with Caroline and Catherine is we get on the iPhone or the iPad and play games. Drives my wife crazy. She doesn’t like it, but both girls like to curl up and play games. In our household, I’m the one in charge of taking the girls to Chuck E. Cheese, and it’s not much of a secret that I don’t mind doing so. I’m trying to get brownie points from [his wife] Heidi for taking them to Chuck E. Cheese, and she’s like, ‘What, are you kidding? You have more fun there than they do.’”

Geeks are cool now, they rule the world. So Cruz’s love for video games is an admission that presidential candidates have only really been able to make in the past few years.

But there is one time a video game was used against Cruz. In Texas’s 2012 Senate Republican primary, David Dewhurst launched an attack ad accusing Cruz of being “PAC-Man.” Dewhurst used the classic video game and accompanying theme song to highlight the funds Cruz received from super PACs in Washington, D.C. The ad wasn’t enough to put Dewhurst over the top, however: Cruz ended up winning by 14 points.