SAN NICOLAS, Mexico (AP) _ Tigermania is here.

The Grammy award-winning Tigres del Norte, the kings of northern ''ranchera'' music, are performing the songs that champion struggling, working-class people.

At a recent concert, the outdoor arena in this town in the northern border state of Nuevo Leon was so tightly packed with fans that those in the front rows had to brace their arms against the stage to keep from being smashed into it.

And fans of all ages struggled through the crowd to hand requests and flowers to the five-man band which has sold more than 20 million albums to date.

It's their music, after all - northern ''ranchera,'' polka-style ballads backed by an accordion, two guitars, a saxophone and drums.

And for the past 18 years, Los Tigres del Norte, the Tigers of the North, have been making it famous in Latin neighborhoods throughout the United States and Central America.

The Grammy award for best Mexican-American performance has opened new doors for Los Tigres, they said. And now they're hoping to be able to perform with artists from the United States. They won for their Grammy-winning album, ''Gracias ... America ... Sin Fronteras,'' or ''Thanks ... America ... Without Borders.''

Their new album, ''Idols of the People,'' contains two songs sung in English and Spanish, marking their first attempt to reach an English-speaking audience.

''It's part of the folklore of the north. It's strictly northern and we don't want it to die,'' said guitar player Raul Hernandez about ranchera music.

Los Tigres - brothers Jorge, Raul and Hernan Hernandez, cousin Oscar Lara and friend Jose Guadalupe Olivo - have recorded 18 albums and performed in 12 movies based on their songs in the two decades since they moved from northwestern coastal Sinaloa state to California seeking a record contract.

''Our music wasn't accepted here in Mexico,'' said Jorge, the oldest Hernandez brother at 37 and leader of the band. ''Nobody would put it on the radio.''

Their lyrics speak of national pride and the realities of their lives: ''I'm proud to be called Mexican, because there is nothing else like it,'' one song says.

They now are residents of San Jose, Calif., and record their music there.

Just teen-agers at the time they left Mexico and without a name for the band, an American immigration agent at the border city of Calexico, Calif., ''baptized'' the group ''Los Tigres del Norte,'' Jorge Hernandez said.

From working-class families, only Jorge finished junior high school and received some formal musical training. They all play music by ear.

Tigres producer, Enrique Frinco writes the lyrics and is the major contributer on the melodies.

Los Tigres started out singing songs of drug deals gone bad, such as the 1971 hit ''Contraband and Betrayal'' that launched their musical career.

Although the drug theme - the smuggler always dies - still is prevalent in their music, they often sing about the status of Mexicans living in the United States, such as their hit, ''The Other Mexico,'' nominated last year for a Grammy.

''Don't criticize me because I live on 'the other side','' the lyrics say.

''I'm not rootless, I live for necessity.

''Already many years since I came as a 'wetback,'

''my customs haven't changed,

''nor my nationality.

''I'm like so many other Mexicans, beaten by life, working under the sun.''

In ''Gracias ... America ... Sin Fronteras,'' the America of which they sing is all of North and South America.

''America is the whole continent, and he who is born here is American,'' the song says.

But the song also says: ''I was born the color of the earth. By inheritance my language is Spanish. In the north, they call me Latin. They don't want to call me American.''

Los Tigres didn't intend to give the impression that America no longer has borders, or that the group was thanking America for not having borders.

''It's a little confusing,'' acknowledged Raul Hernandez, who added that fans often request the song ''America Without Borders.''

''Our idea was to make it known to the people that buy our albums that they should feel American,'' said Jorge Hernandez.

Los Tigres said they were kicked out of restaurants in the United States because they spoke only Spanish when they first began touring in the 1970s. They say Mexican-Americans still are made to feel like second-class citizens in the United States.

''Our songs tell Mexicans that they can triumph in other countries,'' said Jorge Hernandez, ''and not just as laborers, but looking for the best opportunities the country has to offer.''

All married and with children, their music in recent years has included the theme of Mexican-American children and their identity with Mexico. In ''The Gold Cage,'' the father speaks in Spanish and the child in English.

Hernan Hernandez said the best thing about receiving the award is that it's focused more attention on the group.

''To be Mexican and be able to show it to the rest of the world is the best there is,'' he said.