Few musical styles have made as many comebacks, in so short a period of time, as ska – the propulsive Jamaican dance style of the 1960s that became the soundtrack to urban life in Britain in the late 1970s.

This time around, the trademark sound of Jamaican bands like the Skatalites, Prince Buster and King Tubby, combined with turbulent punk-rock, and the pounding beat of hip-hop, has produced a new sound mix in the United states dubbed ‘skacore’.

Skacore might get its biggest boost in this country over the next few weeks, as several bands – including Less Than Jake and the Toasters – began a tour Mar. 26 that will last until May 10. The ‘Ska Against Racism’ concert series, is designed to raise money for the groups Anti-Racist Action, Artists for a Hate-Free America and the Museum of Tolerance.

Several other ska acts, including the Skatalites themselves who – to some argument – claim to have invented the genre – promise to join the Ska Against Racism tour for several dates over the next two months.

Although many skacore bands have been working for years – the Boston-based Mighty Might Bosstones formed in 1985, while New York’s Toasters formed in 1983 – the last few months have witnessed a massive surge in the visibility of ska acts nationwide.

Last summer, the Bosstones earned their first nationwide hit with the propulsive, brassy song ‘The Impression That I Get’, which bases its reflective lyrics on the effort to sympathise with a friend’s tragedy before ending with a typically hopeful coda: “I’m not a coward, I’ve just never been tested/ I like to think that if I was, I would pass.”

Since 1997, several other groups have also scored hits with various ska-derived songs, from Smash Mouth’s ‘Walking on the Sun’, set to a loopy organ groove, to Sugar Ray’s ‘Fly’, a cheerful, guitar-driven song featuring reggae chatting by Jamaican dancehall star Super Cat.

Several of the skacore groups embrace the fast pace and political anger of punk rock, most notably Rancid and Sublime; while others, including No Doubt – a California band which has had the most commercial success – have opted for more conventional pop ballads to accompany the ska tunes.

What all the bands have in common is the trademark ska sound: a chattering guitar line (the sound of which, according to some musicologists, gave rise to the label ‘ska’) wedded to a propulsive bass-and-drum combination that also resembles the 1960s sound of the soul record company Motown.

The U.S. ska bands also have another common feature: they are all more party-oriented and less overtly political than the British bands – including the Specials, the Beat and the Selecter – who recorded for the 2-Tone record label in the 1970s and early 1980s. Instead, many of the bands – as with British band Madness – favour a jaunty, occasionally frenetic, mood in which messages of racial solidarity and working-class laments are subtly stated.

The Bosstones use the combination of party music and anti- racist themes to good effect on their latest album, ‘Let’s Face It’ (on Mercury/Polygram), which includes several songs attacking bigotry and drug use. No Doubt, led by Gwen Stefani – one of the few women singers in skacore – first rose to attention with a song decrying sexist condescension, the sarcastic ‘Just a Girl’.

However, unlike the British ska acts – or their jazzier, and often funnier, Jamaican precursors – U.S. skacore groups embrace the carefree ethics of the young ‘slacker’ generation, with several of the best-known current ska hits (such as Reel Big Fish’s ‘Sell Out’) mocking the very idea of being successful.

Some of the new ska hits are frankly incomprehensible, riding on little more than a sunny spirit and a general mood of tolerance. Sugar Ray’s ‘Fly’, for example, includes such non sequiturs as: “All around the world, statues crumble for me/ Who knows how long I’ve loved you?”

Although the bands are generally anti-racist, the U.S. ska scene is not as integrated as Britain’s was; while the 2-Tone bands, whose checkered suits were their trademark, often featured black and white members, most skacore bands are largely white. (However, some of the most visible acts, like No Doubt, the Bosstones and Reel Big Fish, include several African Americans, Latinos and Asians.)

Still, at a time when most U.S. bands had either divided into a largely white world of rock or a largely black one of rap, skacore’s current success – particularly in U.S. college campuses – is a sign of welcome musical and racial integration amid a cheerful party atmosphere.

About 15 years ago, the Specials lamented the death of the ska scene in London with the lyrics, “This town/ becoming like a ghost town./ All the clubs have been shut down.” Now, thanks to the U.S. scene, ska clubs are open, and bouncing, once more.