The first problem any dramatic adapter of Sinclair Lewis' "Elmer Gantry" has to solve, or at least worry about, is that Lewis' main character is so loathsome few would care to spend time with him.

"He's totally amoral, opportunistic and dumb," said David H. Bell, who directs the new musical now playing at Ford's Theatre. "We've worked very hard at finding out why he should have a musical about him."

And that's just one of the challenges.

But if successful musicals have been made about an Argentine dictator's wife and singing nuns and a raft trip down the Mississippi, why shouldn't one be shaped from Lewis' 1927 lecture of more than 400 pages on hypocrisy in American religion?

In many ways, the creators of this show say, Lewis' restless antihero may find his real home in a musical. The book lacks even one sympathetic character and attained its place in American literature chiefly for its audacity in taking on religion when it was still a largely untouchable topic. The 1960 movie is remembered mostly for Burt Lancaster's Oscar-winning performance, plus the shock of seeing winsome singer Shirley Jones (later typecast in "The Partridge Family" on television) playing a supporting role as a prostitute.

Of the 1970 musical "Gantry," the less said the better, and was. It starred Robert Shaw and Rita Moreno, and ran one night. But it is parent -- or, at least, a stepparent -- of the current musical, in a complicated family tree typical of the theater.

Along the way there was another attempt to dramatize the book, this one inspired by methods used to adapt Dickens' "Nicholas Nickleby" to the stage. Members of Arena Stage worked on that Gantry project in 1982, but never worked out an agreement with Joseph Cates, who owns theatrical rights to Lewis' novel.

About three years ago, however, the composer and lyricist of the 1970 flop, Stan Lebowsky and Fred Tobias, came to Cates with a proposal to revive their show. Since Peter Bell's book had been one of the show's acknowledged liabilities, they hired John Bishop of Circle Repertory Theatre in New York to start from scratch on a new one. Lebowsky and Tobias, for their part, worked on revising their original score.

Ford's executive producer Frankie Hewitt and Bell were intrigued enough to go to New York for a read-through of the show by its authors.

"I liked the book," said Hewitt. "But the music never really got to me. Bishop had gone back to the source material, and the music ... had more of a {contemporary} Broadway sound. Plus they'd been written at different times and it wasn't a real collaborative effort."

Cates had a similar reaction, as did Bell. Each wondered what the next step should be.

Two days after the reading Stan Lebowsky died. Tobias, disheartened, had no wish to continuethe project alone.

At that point Hewitt suggested Mel Marvin, who had written the music and lyrics for "The Portable Pioneer and Prairie Show" at Ford's in 1975, as well as music for a production of "Babbitt" at the Mark Taper Forum. His longtime collaborator Robert Satuloff joined him in writing lyrics; Bell contributed some as well.

So ultimately the entire show was new, and the changes represent much of what has changed in American musical theater over the last 20 years. Even in 1970 most musicals hewed to a fairly rigid formula, which dictated such rules as all third songs being "charm songs," and all endings being happy.

Bell, however, hates charm songs, and the growing maturity of the musical theater meant the adapters of "Elmer Gantry" could shun formulas for a show flavored with the hard-bitten cynicism of Sinclair Lewis.

"When I reread the book I was a bit apprehensive," said Bell. "You can't make it facile, which the musical form seems to demand. Elmer Gantry can be a dark tale of corruption. We hint at that. But this is also the story of Elmer and Sharon ... Bishop's book is unlike any other musical's. You are not left with a world that is in order. It expands the medium of the musical in that it doesn't seek the knee-jerk response."

Bishop's script, like the movie and the previous musical, focuses on the middle third of Lewis' novel, the section about Gantry and his relationship with evangelist Sharon Falconer. She is a charismatic, slightly crazed, but genuinely religious woman; he is the marketing agent who, using witnessing and faith healing, transturns her sincere but shabby revival meetings into a showcase for her unique talents and packs in the crowds. As he says to her:

The way I see it, Sister, people come to us to feel something. Their lives are so removed from the love and spirit of Jesus Christ that they walk surrounded by a desert of their own making..... They want to feel something. They want their guts to churn and their blood to race. They want to feel the heat in their loins tellin' them they're alive ... And that's where we come in.

Heat is also generated in the loins of Gantry and Falconer, with the passion they create on the revival platform surging over them offstage as well.

The character of Gantry's seminary roommate, Frank Shallard, has been lifted from the final chapters of the book as a voice of conscience, personifying the debate between the staid mainstream church and the jazzy "Bible beating" evangelists. As in this exchange:

Shallard: I got to tell you Elmer, I'm not much on revivals. I question whether it really does bring people back to the church.

Gantry: Frank, you ask the pastor of any church in any town we've been to. In some cases the congregation has doubled.

Shallard: But for how long?

Gantry: Hey ol' buddy, our job is to get 'em there. If when they get there the preachin's dry as a wasp nest it ain't our fault.

Shallard: Yes. I've heard about this group. Music, a beautiful woman-evangelist, colorful robes. Sounds like you've sorta liven'd up religion a bit.

Gantry: Well, Frank, I don't think the devil should have all the fun.

Inevitably, the show will be examined for references to current evangelistic events, which in the last year, especially, have played on the American wide screen with a dizzying intensity that no soap opera -- or musical -- could match. Bell, who in the two years of preparing "Elmer Gantry" has become an aficionado of television evangelists, is particularly sensitive to this aspect of the show. On the one hand, it adds immediacy to a 50-year-old book; on the other it presents enormous dangers of parody and imitation.

"We decided that this is not a show about evangelism," he said. "It is about selling as much as anything else."

At the same time, he notes, the "milieu" of the show is evangelism, and "resonances" to current events are inescapable. Bell and the cast found they had to overcome their fascination with television evangelists ("Jimmy Swaggart was high on everyone's list," he said). But the temptation to ape the histrionics of believers had to be resisted.

"We found we had to be nonjudgmental about {evangelists} and the people they are talking to," said Bell. "On one level it's easy to dismiss them as exploitative and immoral; but we found there are many different levels of truth in evangelism and there are some who are really out to minister to a flock."

The group was especially sensitive to "playing" religion because two members of the cast are born-again Christians. Sharon Scruggs, who plays Sharon Falconer with such charisma, is the daughter of a Baptist preacher, Bell said, and undoubtedly brings some "resonances" of her own to the part.

Which brings us back to the character of Elmer Gantry. In the book, Gantry is unable to love anyone or anything but his own survival. Sharon captures his loyalty more than anyone else, although even as she perishes he is thinking about another woman. Bishop and Bell, and actor Casey Biggs in the title role, decided that Gantry's love for Sharon is one -- perhaps the only one -- of his redeeming features, and rather than keep him a character who blunders through life as some sort of venal "organism," they created a Gantry who changes. At the end he is credited with saving people from a fire (in the book he "saves" only those who have already rescued themselves).

He also, in a move that veers well away from Lewis' character, lashes out at plans for the "Garden," a shrine aimed at becoming "The Christian Showplace of America," which he realizes is actually nothing more than a thinly disguised development scheme. "The Garden" -- which does not appear in the book at all -- is perhaps the most direct link to Jim and Tammy Bakker, whose Christian "resort," Heritage USA, includes a prayer room that purports to be a replica of the site of the Last Supper.

"They're buildin' cabins ... a restaurant ..." says Gantry to Frank Shallard. "A formal garden they'll call 'Gethsemane.' I told 'em they oughta have a 'Sermon on the Mount' picnic grounds, pass out free loaves of bread."

But in the end, Gantry spurns a chance to become chief priest of the Garden in favor of taking over Shallard's position as Good Guy. If this seeming redemption sounds a bit like a happy ending, it is also more complex, and more dramatically satisfying in many ways, than the unremitting corruption of Lewis' character.

This production will run at Ford's through May, and then Cates intends to take it to Broadway. He has no investors yet, he said, and it will cost several million to open the show there compared with the $500,000 it cost to produce here. But Cates is determined. "I think we've got a great American musical on our hands," he said confidently. "We are going to New York."