Idealism survives in unlikely precincts of current pop: in hard-core punk, in alternative hip-hop, in albums by old-guard rockers and in the songs of one of Mexico's most popular bands, Maná, which filled the Theater at Madison Square Garden on Monday night with fans who sang along. The band has sold millions of albums across the Americas and Spain, though much of its music is modeled on the sound of an English-speaking band: the Police.

Maná's set was split between songs about love and message songs like "Justicia, Tierra y Libertad" ("Justice, Land and Liberty"), about human rights, and "Cuándo los Ángeles Lloran" ("When the Angels Cry"), about environmentalism. When Fher Olvera sang "Ana," a video screen showed pictures of condoms and statistics about unwanted pregnancy and AIDS; "Ángel de Amor" offered healing love to an abused woman.

The music went bounding along, mostly in catchy tunes that followed the Police's pattern of reggae-flavored verses and pop-rock choruses. Every so often, Maná dipped into more Latin-flavored music: a bouncy norteño tune or a Santana-style salsa-rocker.

With a reedy voice that could easily be mistaken for a Spanish-speaking Sting, Mr. Olvera sang about the pains of love and hope for the world, while behind him Alex González on drums flashily twirled his sticks; every few songs, Mr. González let a drum machine take over as he stood above the band, then leaped onto his drum stool just in time to kick-start the next verse.

For all their earnestness, the songs had a light touch; they were neatly constructed and threaded through with Sergio Vallin's limber guitar lines. The only question was why a band as skillful as Maná is still, after six albums, content to imitate the Police.