(CNN)New Hampshire teens Addy and Emma Nozell have been attending political campaign events in the early voting state of New Hampshire since as long as they can remember. And this summer, they are on a mission to take a selfie with every presidential candidate.
Meet the 'presidential selfie' girls
"Being in New Hampshire and being able to get so close to the candidates is really cool," Addy, 17, told CNN in a phone interview Monday. "I don't think you can do that anywhere else."
In less than two weeks, they have taken selfies with 13 candidates and this Thursday, they have their sights set on Scott Walker and Donald Trump.
"My husband and I fully endorse this challenge," their mother Wendy Thomas told CNN. "Selfies are here to stay and it looks like the candidates are doing a good job of being gracious about taking them. My daughters get a selfie and we get critical thinkers."
Some selfies are harder to get than others but the girls have developed a strategy that has worked, so far.
"We find the hole where no one is standing," Addy explained. "We try to make eye contact with the candidate or talk to their handlers or their helpers."
The girls then seize the opportunity to explain their summer project to campaign staffers.
"Usually, they're very happy to do it," Addy said.
So far, none of the candidates have declined the girls' request.
The most recent presidential selfie is with Ohio Gov. John Kasich, who is expected to announce his presidential bid July 21, retweeted the girls and now follows them on Twitter.
Fifteen-year-old Emma is the one who takes all the selfies and she is adamant about doing it the old-fashioned way.
"You gotta go with the old-school selfie and use the arm," Emma said.
The girls said that their mother has not allowed them to get a selfie stick
"We have a few selfie rules in this house," Thomas said. "You can't stick your tongue out and you have to be respectful."
The girls' first presidential selfie was with New Jersey Gov. Chris Christie, who has spent lots of time in New Hampshire over the last six months.
Christie was standing outside a restaurant in downtown Nashua early this month when the girls approached him.
"He was just standing there on the street and Emma said I should get a selfie with him," Thomas said. "Then Addy turned around and said we should get them with all of them."
The most rewarding selfie for Emma is the one she took with Republican presidential candidate Dr. Ben Carson because before going to a Carson event with her father, her mother told her that she read that Carson doesn't like selfies.
"I told them if he says no, respect that and be prepared for that," Thomas said.
Emma went up to him and asked.
"I know you don't like selfies — I get that but do you mind? I'm doing a project and he was okay with it," said Emma.
Addy's favorite selfie, so far, has been with former Maryland Gov. and Democratic presidential candidate Martin O'Malley.
"I really like O'Malley because after, he came up to our family and he talked to us and when we asked for a seflie he was very energetic and said 'Yeah! Let's take a selfie!'" Addy said.
The girls said that not all the candidates were aware that selfies are now a thing.
"I'd say Rick Perry most out of everyone. He was looking at the cameras in front of us and not ours. He was looking off into the distance," Emma said.
"I don't think he really gets selfies," she added.
The girls anticipate that the most difficult candidates to catch will be with Hillary Clinton, Bernie Sanders and before Thursday, they were also anticipating that getting a selfie with "The Donald," would also be difficult due to his celebrity status.
"[Sanders'] popularity here is going through the roof. His events are getting bigger and bigger," said Thomas.
The girls have met Clinton before while she campaigned during the 2008 Democratic primary but they have not met her since she became secretary of state and Emma said that their family "loves Hillary."
Before there were selfies and before they were teenagers, the Nozell girls were already meeting candidates and politicians on the campaign trail.
Neither of the girls will be able to vote in the primary but Addy will be able to vote in the general election for the first time.
"I kind of lean more towards Democrats," Addy said but added that "some Republicans seem to make more points that I can relate to."
One of their brothers is at Norwich University in Vermont and, "for the first time these girls are really paying attention to military strategy and what's happening in the Middle East where there's a really good change their brother could go," said Thomas.
The girls have not selected a favorite candidate yet, and they say that they are looking forward to hearing from everybody.
Overall, Thomas said that they have respect for all the candidates.
"Politicians really recognize that the landscape has changed," Thomas said. "If you're not willing to take selfies, you're going to lose a lot of young support. And while a vote doesn't really hang on a selfie, it does it hang on interest."
And for those attending political campaign events in New Hampshire, look out for the presidential selfie girls.