Reese Witherspoon has turned herself into Hollywood's current A-list sweetheart by playing determined blondes who are not as dumb as they seem.

Her larger-than-life belles in Election and Legally Blonde transformed the 26-year-old Tennessee native into one of the most sought-after actresses of her generation.

In many ways there's quite a bit of the real person in those characters, and the humour comes from their believability. Witherspoon is a serious actress who seems to have become a comedy star by accident.

But you shouldn't underestimate this petite little bundle of energy juggling motherhood and stardom. She is no overnight studio creation, and Witherspoon has been working for this for over a decade, when she left her Nashville roots and headed for Tinseltown as a precocious young teen.

That's why Witherspoon is so happy that her latest film Sweet Home Alabama is attracting a lot of attention. She may be a Hollywood princess now, married to actor Ryan Phillippe and with her own production company, but she's still a Southern girl at heart.

This time she gets to go back to her roots. The romantic comedy features Witherspoon as Melanie Carmichael who fled the South for New York, but returns to come to terms with her background.

"It reminded me of what I went through coming from Nashville and moving to Los Angeles and rejecting my background to some extent," she explains.

"I understand where this character's coming from. Growing up I was embarrassed about saying I was from the South."

The good things the South is known for are real, she maintains. The old world manners, the sense of community. Witherspoon can turn on the Southern charm at the drop of a hat. They may be clichs, but in many ways they're real clichs.

"I liked the idea of someone having to go back and make peace with who they really are and accept it," she says. "I represent those values people identify with the South, that certain honesty and sincerity."

Part of Melanie's homecoming is to deal with a man (Josh Lucas) who she married as a teen and now wants to divorce.

It was a good opportunity to play up the eccentricities associated with the Southern culture, she says. "I wanted to celebrate rather than ridicule it. I come from an eccentric family. I mean my father's a doctor who rides around on a Harley and wears camouflage gear."

She also got a chance to slip back into a natural Southern accent, particularly after the ordeal of having to do a passable English accent on her last production The Importance of Being Earnest.

"I really wish I could have held on to my Earnest accent but it was hard," she admits. "It helped on this film that my brother was with me as my driver. We'd fight on the way to work and my Southern accent comes out when I'm a bit angry."

Sweet Home Alabama may be more comedy than social study, but there's a good lesson for every young person in the story, she adds.

"I think it's for every young person who goes through this, rejecting their upbringing or where they're from, and then having to ultimately accept who they really are."

Director Andy Tennant says Witherspoon gives a wonderful performance that really fits the character's inner struggle. One monologue starts with a smile and ends with tears. "You can see all her thoughts so I didn't cut it, I wanted everyone to see Reese's performance."

Sweet Home Alabama co-star Candice Bergen suggests Witherspoon has now become America's Sweetheart. Hollywood certainly thinks so because her $5m fee for this film has leapt to a reported $15m for her Legally Blonde sequel Red White and Blonde. Tennant is also writing a romantic adventure with her in mind.

But Witherspoon says she has paid her dues since her eye-catching, unintentionally funny teen killer role in Freeway in 1996. Her smart virgin in Cruel Intentions' was her breakthrough role, until Election became a commercial and critical hit. She gave up on plans to study literature at Stanford when she was offered a role opposite Paul Newman in Twilight four years ago.

"I've been in this business 13 years and I've been a snail crawling my way to this point. You have to tolerate a lot of rejection and still keep your self-worth intact. All the things I've been through have helped me appreciate the moment I'm in."

Arriving in Hollywood at the age of 14 put her through the mill, she admits. "I don't think you have the emotional maturity to deal with a lot of the situations you're put in. There are a lot of ulterior motivations you don't necessarily understand. I wouldn't let my own daughter get into this business until she's 18."

But her dogged resilience paid off. Life now includes a Los Angeles mansion, three-year-old daughter Ava Elizabeth with Phillippe, who she married in 1999, and her own production company, Type A Films.