When Portuguese singer Mariza calls herself a "fadista," she's not referring to her penchant for flamboyant outfits or her chic hairstyle of bleach-blond waves. She sings fado, which simply defined, is the blues of Portugal. But a more succinct description comes from author Lawton McCawl, in his book Portugal for Two: "Fado is the spontaneous poetry of the human heart, shared with an audience that feels and understands."

It's a sentiment that Mariza shares. "Fado is a feeling, it's not really music," she said in a phone interview earlier this week during a tour stop in Minneapolis. "When I sing, I feel everything. Fado is completely me. I don't have to think, it's automatic."

Literally translated, fado means "fate." Mariza, a native of Mozambique who grew up in Lisbon, could have hardly predicted the good fortune that fate has dealt her. Though she has made only two albums, "Fado em Mim" (2002)--the title means "Fado and Me"--and the just-released "Fado Curvo," critics have hailed Mariza as successor to the legendary Amalia Rodrigues (1920-1999). Universally acclaimed as the queen of fado, Rodrigues reinvented the centuries-old genre by fusing the rural and urban styles of Lisbon and Coimbra (the medieval capital of Portugal). Such was her influence that when Rodrigues died, Prime Minister Antonio Guterres declared three days of national mourning for "the voice of Portugal."

To her credit, Mariza downplays any comparisons. "It's a little bit scary," she said. "They are talking about me like I'm really, really good. But that creates expectations, it makes responsibilities. It's a huge compliment, comparing me with her. But they remember Amalia at her peak, when she was 40 years old. I am 29."

In any case, Amalia remains the standard for all fadistas; in the world of fado, she represents a dividing line not unlike the birth of Christ. "When we talk about fado, we have after Amalia and before Amalia," Mariza said. "But Amalia is the diva, she is the icon of fado. She had a different way of singing, she had a different way of being onstage. She was a complete diva [in every sense of the word]."

On her first disc, Mariza covered many songs that Rodrigues popularized, such as "Barco Negro" and "Maria Lisboa." For "Fado Curvo," Mariza chose only one Amalia tune, the somewhat upbeat "Primavera." "It's my favorite. Fado is normally melancholy. But there are lots of happy fados, too," she said. "Besides, you can't do all your records or concerts always crying and [displaying] all those [sorts] of emotions. Otherwise, people are always down. So that's why I decided to make new fados. That is what led to the new songs on this disc."

She's evolving, like the art form itself. The Portuguese used to speak of the three "Fs"--fado, the saint Fatima and football (what Americans call soccer). Fado was also associated with the 40-year dictatorship of Antonio Salazar, whose regime finally collapsed in the mid-'70s. "With the end of the old regime, fado suffered a little because people said, 'Fado is for dead politicians, for old people.' By the '80s, fado was down, people had forgotten about it. You had to go to traditional neighborhoods to hear it."

Like many folk genres, fado has experienced a revival, thanks to Mariza, and Portuguese colleagues such as Cristina Branco and Misia. "Lisbon is changing all the time," Mariza said. "Now you can hear fado everywhere, on almost every corner. You even see kids in in streets singing it."

Though as a child, Mariza used to sing in the streets herself, these days she sells out venues all over the world. (At press time, her performance Sunday, presented by Hothouse, was scheduled to go on, despite the club's closure last week over a licensing dispute. Check the Web site www.hothouse.net for updates.) "I love performing in all sizes of theaters," she said. "It's such a honor being onstage and having people relate to you."

After her U.S. tour, she returns to Europe for more concerts. "I hope to be able to finish the year," she said, laughing. "We are ... how do you say in English ... working like dogs! I miss my family, but when you are in love with what you're doing, it helps make it OK."

Speaking of her family, what must they think of her unique look? Most fado singers dress in black, shrouded by shawls, with long dark hair flowing over their shoulders. Imagine Natasha of "Rocky & Bullwinkle" fame, only clad in embroidered veils and heavy wool skirts, and you'll have a fair approximation of the typical fadista garb.

For now, Mariza enjoys being a blond. "Maybe when I get older, I will switch to a more traditional style," she said, laughing. "When you go to a special occasion, like a wedding, you put on your best clothes, you do it in our way. That's how I explain my look."

So expect Mariza to keep approaching her art in her own way, on her own terms. She envisions a long career, perhaps like Amalia's, but with her own distinct signature. "I could sing other kinds of music, but fado is me, it's like breathing," she said. "Fado is my music, fado is my culture, and I belong to it."