It was hot and close enough inside the Balcony Bar on Thursday night to pass for a tent revival meeting, a fact that did not escape the notice of singer Diane Birch.

"Welcome to the church of Birch," she quipped, before rolling into a gospel-flavored introduction to "Fire Escape."

The invitation to worship at Birch's altar was part overreaching and part tongue-in-cheek, and it had a hint of blasphemy about it as well. The offspring of an itinerant South African preacher who settled in the Pacific Northwest when she was 13, Birch rebelled by going Goth, sneaking out of the house to hang out in cemeteries.

Apart from her bangs and conspicuous eye shadow, there's not much to mark Birch as a former aficionado of all things dark and gloomy.

Rather than the melancholy chill of Joy Division and the Cure, her songs draw on the mellow soul of Laura Nyro and Carole King, with, in "Ariel," just a smattering of Elton John.

A year after the release of her first album, Bible Belt, Birch is still climbing uphill; Thursday's show was originally planned for the Trocadero's main room, but was moved upstairs to the far smaller Balcony in response to slow ticket sales. The audience that showed up was full of diehard fans who visibly moved Birch with their enthusiastic sing-alongs.

Backed by a tight four-piece band that added swooping bass lines and thrumming organ to Birch's electric piano, she spent an hour playing most of Bible Belt as well as a pair of choice covers.

After sending her band into the wings - "normally this is the part where they leave the stage," she remarked, "but there's nowhere for them to go" - Birch laid down a mellow and initially unrecognizable version of Haddaway's "What Is Love," replacing disco synths with languorous piano.

Hall and Oates' "Rich Girl" came by way of an audience request, but the impromptu full-band encore came together quickly, with only a few bumps on the way to the finish. If it wasn't the spirit that moved her, Birch still seemed to be in touch with something bigger than herself.

Maybe it was Daryl Hall.