If you think the 2008 presidential campaign field is crowded and unpredictable, take a look at the competition for America’s next first children.

The total number of entrants: 34.

Not only do they range in age from 5 to 48, but the children of the remaining 12 presidential candidates come from as far away as Bangladesh, count “music producer” and “elementary school student” among their day jobs, and have relationships with their political parents that span the continuum from estrangement to entitlement.

Such a colorful group throws wide open the possibilities for the nation’s fascination with what might be the second-toughest job in the country — living in the shadow of a presidential parent.

“There are people waiting for you to mess up so that they can write about it,” says Sarah Huckabee, the 25-year-old daughter of GOP candidate Mike Huckabee, former governor of Arkansas. “I think that comes with the territory.”

Sarah, who is volunteering full time for her father, phones from the road after having been awake for 36 hours. She explains that if her family does move in to the White House, it would not be the first time she would be in the public eye.

After all, she says, she spent much of her childhood in the Arkansas governor’s mansion.

The young woman is a former Education Department staffer and graduate of her father’s alma mater, Ouachita Baptist University, a conservative Christian school set in a county that prohibits alcohol, even if you are 21 or older.

The school separates dorms by sex, but it does allow students of the opposite sex to visit each other — something Sarah worked on as student body president. No matter what happens with her father’s bid, she says, she wants to make a career of working on political campaigns.

However young or old, agreeable or aloof ­they may be, the next first kids may find that being a part of the White House is tough work.

“As this campaign gets close to the end, whoever wins the election, their kids are going to be … huge celebrities,” says Doug Wead, the author of All the Presidents’ Children and an alumnus of both the George H.W. Bush and George W. Bush White Houses.

But fame comes with a price.

Wead says his research on first children shows that, regardless of age, they all go through the same identity crisis that centers on self-definition in relation to their presidential parents.

“It’s a crisis of ‘Who am I?’ ” he explains.

“And some of them react, ‘I’m not you,’ so they change their name. They join the opposite political party,” Wead says, pointing to Ronald Reagan’s daughter Patti Davis.

As if intra-family turmoil were not enough, there are also the country’s comedians to deal with.

Chelsea Clinton endured humiliating public experiences when “Saturday Night Live” parodied her pubescent growing pains. Andrew Giuliani, meanwhile, has already been the target of the same sketch-comedy show. In a skit recreating Rudy Giuliani’s swearing-in as mayor of New York City, Chris Farley played a young Andrew, wildly stealing the scene and generally upstaging his father.

Is such treatment too harsh? It depends, say political humorists.

“Our general feeling is it’s hard enough being a kid without your parents’ job factored in,” says Elaina Newport, a producer for The Capitol Steps. She could not recall a time when her comedy troupe targeted first children without just cause.

Kate Clinton, a comedian now on her “Hilarity Clinton ’08” tour, agrees.

“With the kids, I feel like, haven’t they suffered enough that their parents are away or that they have to decamp to Iowa?” she says.

Both satirists note an exception: when the children volunteer themselves for public scrutiny.

Well-known examples include the Bush twins’ underage drinking escapades and, later, Jenna Bush sticking her tongue out at the paparazzi. Both incidents resulted in unflattering press.

An example from this campaign: The five Romney brothers quit their day jobs to campaign for their father, and Republican candidate Mitt Romney unwittingly compared his smiling offspring to America’s service members. This, too, resulted in unflattering press.

“Gag me with a forklift,” Kate Clinton says of the incident. She regards the Romney brothers as an exceptional situation and would use them in her skits. “In terms of comedy, I would probably feel it fair game that, if [the candidates] have used their kids as props, I will too.”

Were any hard lessons learned from the Romney trip-up?

“You’ve got to be very careful about what you say and how you say it,” says Josh Romney, 32, who conducted our phone interview while riding an exercise bike at the Red Rock Hotel in Las Vegas.   

The Salt Lake City-based real-estate developer says he and his brothers have been so busy campaigning that they have not thought much about what it would be like to assume first children roles. None would move to Washington, he says, but he could see himself helping his mother, Ann, run humanitarian efforts out of the East Wing.

The younger campaign children are subject to the whimsy of their parents. Sen. Barack Obama (D-Ill.) has paraded his two daughters, Malia, 8, and Natasha, 6, in front of cameras often enough to foster the public’s familiarity with their faces.

The same goes for former Sen. John Edwards’s (N.C.) younger children, Emma Claire, 9, and Jack, 7. Meanwhile, the Democratic candidate’s older daughter, Cate, 25, a Harvard University law student, has put herself into public life as one of her father’s main campaigners.    

The potential first children are already showing varying degrees of media availability. Sarah Huckabee and Josh and Tagg Romney provided The Hill with their cell phone numbers or e-mail addresses.

The Edwards campaign did not return phone calls to get in touch with Cate. Meghan McCain also did not return various interview requests submitted through her campaign blog, Mccainblogette.com.

The first twins were unreachable, too, even though Jenna’s media availability has taken a 180-degree turn of late. She has done recent interviews with Ellen DeGeneres and Barbara Walters, primarily to promote her book, Ana’s Story, and her recent engagement to Henry Hager has also been a buzz topic.

Sarah Huckabee expressed what many potential first children might be thinking right about now: “Maybe we’re not all that interesting after all. And maybe there’s not much to write about. That would be my hope, anyway.”

Jenna? Barbara? Do either of you want to take that one?