How One Little Girl Is Raising Her Voice In a Big Way for Chris Christie

— -- One of Chris Christie’s biggest supporters is also among his smallest.

Sienna Szarek, 7, standing 3-foot-8, is one of the loudest -- and most recognizable -- voices besides Christie himself at the Republican presidential candidate’s New Hampshire campaign events.

At the beginning of nearly every town hall meeting in the Granite State, Sienna takes the microphone ahead of the New Jersey governor to perform the National Anthem with so much passion that the audience even loves it when she goes off key.

“He said that I was the campaign’s secret weapon,” Sienna said of Christie, who has given Sienna an exclusive gig to unleash her inner-performer at his town halls.

“I like singing because it’s like really fun, I get to actually let out everything I have inside me,” she told ABC News in an interview.

Sienna’s father John, who jokingly refers to himself “Sienna’s chauffeur,” explains that his daughter’s participation is about the performance more than it is politics.

“If your daughter is a gymnast you bring her to the gym, if your daughter likes to swim you bring her to the pool, what if your daughter likes to perform in front of 500 people?” Szarek told ABC News.

When she’s not wielding the microphone at Christie’s town halls, Sienna finds other ways to redirect her larger-than-life personality -– at times standing on a chair beside Christie’s staffer who controls the sound board as if to offer direction, skipping around the room as Christie works the room, and even adding music to the task of handling out yard signs, at times singing, “Who wants a yard sign?”

Over the course of the primary, Sienna has lent her voice to several other Republican candidates besides Christie -– everyone from Jeb Bush to Carly Fiorina -- but in recent weeks, she can only be found at Christie’s events.

“The political season is a fantastic time to be singing and performing, and Gov. Christie has given Sienna just a ton of opportunities and that’s why we’ve kind of gone exclusive with Gov. Christie,” John Szarek explained.

While Szarek emphasizes that his daughter’s participation began principally as a stage for her to perform, Christie has won over the family’s votes in the process.

“The lines kind of got crossed a little bit, you spend a lot of time with these people and you kind you really like them and that’s happened with Gov. Christie,” he explains.

If you ask Sienna who’s she’s backing for president, with her voice if not yet her vote, there’s only one man for job: “I’m totally for Gov. Christie, he’s the only one who likes me so much.”

Beyond her love for the stage, Sienna says her gig as the source of the Christie campaign’s musical entertainment has a deeper meaning.

“I get to meet a lot of people and it has a lot of meaning to me, I see veterans, and I give them veteran cards,” said Sienna, explaining that meeting veterans is her favorite part of the gig because “they fight for us, they protect us.”

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