Mississippi-born singer and guitarist Johnny Rawls is a relentless road warrior who has performed bluesy soul and gospel songs around the nation since the late 1960s. He’s never had a crossover hit, but Rawls impressed old-school R&B connoisseurs as vocalist O.V. Wright’s bandleader in the 1970s and with a series of albums released both under his own name and with collaborators. Since 1994, Rawls has been especially busy rendering his roadhouse and church-derived numbers, many self-penned, on various small labels. His most recent effort, Soul Brothers, a duo release with vocalist Otis Clay, includes covers of soul standards like “What Becomes of the Broken Hearted.” But it’s the earthy tunes that Rawls had a hand in creating, like “Voodoo Queen,” that prove most interesting and invigorating. On a prior album, Memphis Still Got Soul, Rawls releases a storm of emotion on “Stop the Rain,” a slow-dance tearjerker on which he cries about a woman dumping him for another man. Possessing a gritty yet passionate voice, Rawls masters both funky, upbeat Stax-rooted tracks and drown-in-your-whiskey-glass ballads, transcending traditional bar band formulas. Johnny Rawls performs at 10 p.m. at Madam’s Organ, 2461 18th St. NW. $5. (202) 667-5370. madamsorgan.com.