The package is small -- just 140 pages and sized at 53/4"x72/3" -- but The Invitation (Harper San Francisco, May), a meditative poem/essay written by Oriah Mountain Dreamer, is shaping up to be some pretty decent-sized publishing.

"We haven't had something take off like this through word of mouth in years," said HarperSF marketing director Karen Bouris.

Since it hit stores in early May, the book has already gone back to print twice, jumping from 12,000 to 33,000 copies shipped, and "reorders are pouring in," Bouris said.

"It d sn't interest me what you do for a living. I want to know what you ache for, and if you dare to dream of meeting your heart's longing," begins The Invitation. The book was born one night in 1994 when Mountain Dreamer, a Toronto-based teacher of creative writing and women's spirituality, came home unsettled by one of those overly slick, shallow parties and wrote a poem about depth and meaning and honesty. She included it a year later in a chapbook of poetry that she used for evening readings.

"After that," she said, "it took on a life of its own. People started copying it and sharing it, reading it at weddings and funerals, passing it around on the Internet, and it began a process of traveling on its own all around the world." The Internet momentum is similar to that for Mary Schmich's Wear Sunscreen: A Primer for Real Life, a sleeper hit for Andrews McMeel.

Although Mountain Dreamer had published Confessions of a Spiritual Thrill Seeker in 1987 with a small Canadian press, this was the first time that she had written anything with such public appeal. In 1996, agent J Durepos contacted her to request that the poem be included in Jean Houston's Passion for the Possible (HarperSF, 1998). He also suggested she develop The Invitation into a stand-alone book.

It took her 12 weeks to make that expansion -- a week to add commentary to each section of her poem. "I wanted to offer something emotionally intense that moved closer to the experience of what the poem was talking about," she said.

HarperSF, which bought the book for five figures, did not initially plan a major publicity push. "We planned a direct-marketing campaign to independent booksellers, and hoped good in-store positioning would sell it," Bouris said.

The response to the book, however, has been so overwhelming that HarperSF is now rolling out a much expanded campaign. Mountain Dreamer will now do a national radio tour, with an interview on NPR's New Dimensions scheduled to air on June 24. The book will be featured in NPR spot ads in seven western cities, including Santa Fe, Denver and L.A. Mountain Dreamer will also do a limited book tour, primarily in the Bay Area. And the publisher is making available nationwide T-shirts that San Francisco-based distributor Bookpeople has created to promote this hot title.