"My butt does not sell records to 9-year-olds," says John Popper, Blues Traveler's oversized singer, harmonica player and resident wisecracker. He's explaining why he and his bandmates have only cameo roles in their popular "Run-Around" video - the quartet is glimpsed performing behind a curtain while rambunctious teen boys mime the hit onstage. "The point is we're good musicians, we're proud of that and we're not the most physically attractive guys in the world," says Popper, 28. "George Michael's butt is perfectly round, and 9-year-olds care about that. Videos are about image. It's an art for some people are good at, but we'd be stupid to assume we're good at it because we're in a band." Groupie magnets they're not. The band's self-deprecating video pokes fun at its lack of sex appeal, but Blues Traveler is getting the last laugh. Without videogenic derrieres, they dominate a thriving sub-genre of upbeat, anti-image, improvisational rock. The quartet's fourth album, four, recently broke Billboard's top 10 and has sold more than 2 million copies since its release last September, largely on the strength of "Run-Around," a catchy pop-blues tune and lyrical cousin of Bruce Springsteen's "Rosalita." The single has cracked several radio formats, from alternative rock to boomer-aimed adult alternative, and the video is a mainstay on MTV and VH1, overshadowing hipper and cuter acts with a fraction of Traveler's musicianship. "I honestly can't take videos seriously," says guitarist Chan Kinchla, 26. "It's just not natural. We look dorky. To sit around all day and play the same guitar part for the 50th time like you mean it is a pain. "It's cool that we've been successful without working on an image. In a way, MTV's been detrimental to bands. It's bum-rushed a lot of them into a spotlight they're not ready for. Far too many of them suck." Formed eight years ago, Blues Traveler earned respect the old-fashioned way: They toured non-stop. Labeled neo-hippies alongside the nomadic Phish, Rusted Root and Dave Matthews Band, the equally jam-oriented Blues Traveler built a core following onstage without radio support. They were fearless and seasoned road warriors when they stormed Woodstock '94, drawing national notice for Popper's harmonica take on Jimi Hendrix's classic version of "The Star-Spangled Banner." Exposure snowballed with "Run-Around," yet the band continued its city-by-city live assault. It currently stars with the Black Crowes, Ziggy Marley and a slew of rising acts on the 23-city HORDE festival, founded by Popper in 1992. Trashed and praised as Grateful Dead soundalikes, Traveler and its ilk clearly appeal to an audience thirsting for accomplished live players." This band could perform with washboards and telephone wires strung on a fence," says VH1 vice president Wayne Isaak, who was the band's publicist at A&M Records during Traveler's hungry years. "They started as good musicians and turned into great musicians. Popper is a virtuoso, an amazing musical machine. I've seen him do everything from War's "Low Rider" to Led Zeppelin's "When the Levee Breaks." The channel began playing "Run-Around" 27 weeks ago, then added a clip of a live acoustic version the band played in VH1's studio. A&M issued it to radio as a promotional CD. "The first hit is always the most difficult," says A&M chief Al Cafaro. "Now they've broken that barrier, and the excitement has exploded." Breaking a band that prizes on-stage improvisation over crafting radio-friendly hits "is a challenge, but you want artists that connect at the live end, because that's real," Cafaro says. "Blues Traveler's essence is that wild abandon. On one level, they really are a bunch of roving vagabond minstrels who live through their music. That kind of heart-and-soul dynamic is not unlike the Grateful Dead. They play until they drop." Popper and drummer Brendan Hill, 25, met in Princeton, NJ, 12 years ago. They enlisted bassist Bobby Sheehan, 27, and Kinchla, who turned to guitar after a knee injury derailed his football career. "I delivered furniture and sold Time-Life books by phone while these knuckleheads were in school getting a free ride," Kinchla recalls. The band relocated to Brooklyn and worked the Manhattan club circuit. They were shaped by a wide range of influences, none greater than New York itself. "We saw rap, funk, blues, jazz, country," Kinchla says. "It really opened our minds." Former A&M talent scout Patrick Clifford recruited the band seven years ago. A 1990 eponymous debut and 1991 follow-up Travelers and Thieves sold modestly. Hopes were high that third effort Save His Soul would vastly expand the fan base. But during recording in late 1992, Popper plowed his motorcycle into a Plymouth Duster and spent much of the next year in a wheelchair. "We'd just talked A&M into giving us all this money to produce our own record for the first time," Kinchla says. "So a month after the accident, we were back in the studio." During the next tour, Popper performed from a wheelchair and traveled in a separate van because he couldn't board the band's bus. "In every sense of the word, we were crippled," says Popper, who walks with a cane and only recently regained the ability to climb stairs. His health problems don't end there. "I gotta lose 100 pounds or I'm gonna die," he says; that's his doctor's prognosis. "I weigh a hell of a lot, probably around 350 pounds. I've just gone over to being diabetic, so now I have to take pills." Popper is equally frank about chart-top competition. "I think Michael Jackson is a great singer, but when you listen to the songs he's written, there's nothing there," he opines. "And I have four words about Green Day: People miss the Jam." He's also irked by mediocre harmonica players. "Bob Dylan sent a message that anyone who could inhale and exhale could play the harmonica," he says. "Dylan's a great poet, he's a genius, but he's a lousy harp player. So's Neil Young. The harp's been treated as a toy for too long." Though musically apolitical, Popper and company don't shy from unpopular stands. They're in sync with rock's leftists on the topic of Bob Dole - Kinchla calls him "an idiot loose cannon who's going to self-destruct if he keeps blowing his wad." But they veer from the party line on presidential candidates: Bill Clinton is ineffectual, and Democrats are wishy-washy do-gooders. "There's gotta be somebody who's awake and a good leader," Popper says. "Dole could do it if he'd calm down. The Democrats all want to be your friend. The Republicans just want the money. I appreciate their honesty and single-mindedness. I'm a new conservative. I was a bleeding-heart liberal until I got a job." That job is reaping fame and profits never imagined by Blues Traveler. Or their fans, a largely college-going crowd that Kinchla describes as "way too white for my tastes." "There have been a few cries of sell-out," he says. "But it's not a vicious assault. Our fans are just reminding us not to lose our heads. If you pay too much attention to marketing yourself, you get distracted and lose what's important - to play better and work on the music." If the Travelers stop growing creatively, they hope to recognize the end of the road and gracefully pull over. Popper doesn't want to evolve into a retread act devoid of fresh ideas. "That's when the tree is dead and the branches don't know it yet," he says.