The archetypal Bar Band Making It Big is either George Thorogood & The Destroyers or The Fabulous Thunderbirds, brawny blues rockers (remember Blueshammer?) who cut their teeth on classic tunes while wowing party-hard audiences at one smoky club after another. Eventually, they both penned some tunes of their own, blew up and never looked back. Yet the bar band is not permanently fixed to classic modes of blues and rock. It's also a creature of evolution, a staple of regional entertainment whose set lists are in perpetual evolution, so as to reflect the larger trends in American pop music.
Beginning in the late 1980s, a new kind of Bar Band Making It Big emerged. Honing their chops on America's sprawling college-bar circuit (equally party-hard, equally smoky -- at least back then), these bands knew their classic rock covers, yet they were also modern and hip. They came of age loving R.E.M., U2, The Pretenders, The Replacements and other alt rock staples just as much as they did The Rolling Stones, Van Morrison and The Beatles.
You can hear this mixture of the old and new in Train and Counting Crows. Other groups, Collective Soul and Matchbox Twenty among them, were young enough to reflect grunge's push into the mainstream; a few were (vaguely) alternative themselves. Years before "Iris," a young Goo Goo Dolls played punk shows; Gin Blossoms weren't nearly that D.I.Y., yet their jangly sound betrayed their knowledge of the esoteric power pop of Big Star and Alex Chilton.
The late '80s also gave birth to another permutation of the modern bar band: the jam band. Though Spin Doctors, Blues Traveler and their ilk will forever be linked with the neo-hippie summer festival H.O.R.D.E., their original home base, prefame, was the greater New York City/New Jersey area, where they predominantly played bars, including the now-defunct Wetlands.
Where is the American bar band headed in the 21st century? If Augustana and The Fray are any indication, expect an even more pronounced U2 (and Coldplay) influence -- piano rock, in other words. But it's going to reflect the commercialization of indie rock, too. So yeah, be on the lookout for Indie Hammer somewhere down the line.