Chris Christie’s 82-Year-Old Dad Has Become His Most Effective Super-Volunteer

— -- It’s 9:30 a.m. on an icy cold Saturday morning in Dover, New Hampshire, and Chris Christie’s most dedicated volunteer is already hitting the pavement, going door-to-door in what will be a full day of canvassing for the man he believes should be the next President of the United States: His son.

Dressed in a red zip-up winter coat and a scarf draped around his neck, the New Jersey governor’s 82-year-old father, Bill Christie, makes his way across another ice-packed driveway at a confident clip to climb the steps of the sixth house he’s visited that morning with no answer at the door. It’s just the start of the some 160 doors he knocks on in an average day.

“What are we 0-for-6? At least we put the flier up, they know we came,” he remarks after hanging a flier on the door and making his way back to a car driven by a Portsmouth GOP chair and Christie supporter John Formella.

Back in the car, Christie pulls out his phone to reference an app that shows the campaign which door to knock on next, based on Republican and independent registration information.

“I come up here to help Chris, and they couldn’t stop me if they tried. I’d come and do it on my own actually,” Bill Christie told ABC News. “It’s a labor of love.”

By the eighth house, an elderly woman dressed in a pink nightgown opens the door and invites Christie inside after he introduces himself as the governor’s father. She then calls out to her husband to come meet him as well.

“I didn’t realize you were that old,” the man remarks to Christie following their introduction in his living room. He tells Christie he’s “pretty much decided” to back his son in the first-in-the nation primary, while wife says she’s definitely voting for him.

“That was worth the wait wasn’t it?” Christie says back outside, and updating the app to reflect that there is one Christie supporter and another undecided living in the house.

“They’re always amazed that a little bit of an older man is out here working for his son,” Christie says of his canvassing experience. “To me, it’s the thing to do. It’s been that way all our lives, though. We never missed a baseball game, and I’m not going to miss this -- that’s for sure.”

As he makes his way from house to house, Christie’s phone periodically dings with the notice of a new text message.

“He’s still tweeting,” says Christie, who has text message alerts set up to be notified every time his son tweets.

This is what the last four weekends have been like for Bill Christie, who has been traveling up from New Jersey with a group of Christie super-volunteers to canvass for his son, in rain or shine.

On a day that brought cold rain and winds, Christie donned a yellow rain slicker and preserved.

“That day was bad and another day when the ice was very bad and I had sneakers on, and I had wet ankles, wet socks all the way home, windy and wet. That was the worst,” Christie said.

While canvassing is the less glamorous side of campaign work -- and is sometimes accompanied by unpleasant weather conditions or an occasionally unfriendly human encounter -- it’s the adversities of the experience that Christie says help bring him closer to his son.

“I think it puts you in the same category as what he puts up with. He’s going to deal with some unfriendly people. To me it’s like experiencing what he goes through, especially when he started,” Christie said.

“Dad did not like his slow start but I’m certainly enjoying it now,” he adds, referencing the progress of his son’s campaign.

ABC News' Lindsey Jacobson contributed to the production of this video.