Herman Cain, fast-food millionaire turned U.S. Senate candidate, fixed his gaze on the semicircle crowding around him at the local political hangout and grinned. It was showtime. The women in the red-white-and-blue blouses had set aside their fried chicken plates and ambled into the lobby of the Plaza restaurant, idling attentively beneath the autographed picture of former House speaker Newt Gingrich.

"If you want to define conservative," Cain told them, punching up that last word for emphasis, "I'll spell it for you: C-A-I-N."

Cain, a former Burger King executive who owned Godfather's Pizza for 15 years before selling the chain in December, has chosen the most unconventional of stages for his political debut. In a state where more than half the Democratic voters are black, he is bidding to become the first African American elected to the U.S. Senate from the Deep South since Reconstruction by running as a Republican -- and a highly conservative Republican at that.

He has no delusions of appealing to masses of African American voters, saying he would expect to draw some support from black Democrats, but "no avalanche," if he pulls an upset over the front-runner, Rep. Johnny Isakson (R-Ga.), and makes it into the general election. In recent years, two African Americans have been elected to Georgia statewide offices -- attorney general and labor commissioner -- though both are Democrats.

"We're as redneck as it comes, but we've come a long way," said Kay Godwin, a Cain supporter who also serves as a regional grass-roots coordinator for President Bush's reelection campaign.

Appealing to the mostly white, rural and small-town audiences that turn out for his speeches, Cain touts his opposition to abortion and his desire to abolish the Internal Revenue Service on damply humid courthouse squares, under century-old oaks, anywhere he can find someone who will listen.

It is the mantra of his campaign, even as it is the mantra of his opponents. With Georgia's Democratic Party in disarray, Cain has spent $775,000 of his own money to nudge the Republican campaign for Senate into a headlong sprint to the right, a contest to see who can wear the label: most conservative of all.

Georgia is among five southern states where Senate seats held by Democrats are coming open this year. Republican leaders are confident they can win the seat in Georgia, in light of the state's recent shift toward the GOP after more than 130 years of solid Democratic control. Democrats seeking the nomination include first-term Rep. Denise L. Majette and millionaire businessman Cliff Oxford.

At a radio debate, Isakson declares he is "a conservative who delivers." Another candidate, Rep. Mac Collins (R-Ga.), claims the conservative mantle for himself and warns listeners: "It's no time to send a moderate to Congress."

"Everybody is trying to out-conservative each other," said Daniel Becker, political action committee director of Georgia Right To Life.

Cain, 58, has used polished television commercials to make abortion the signature issue in the campaign and to establish himself as the aggressor in the run-up to Tuesday's primary. As the primary season progresses, abortion is increasingly becoming a touchstone in races throughout the country.

Former representative Tom Coburn, a Republican candidate for Senate in Oklahoma, has called for doctors who perform abortions to be sentenced to the death penalty. Abortion rights advocates in Washington state have slammed Democratic House candidate Dave Ross for favoring parental consent before teenagers can get abortions.

In the mathematics of Republican politics in Georgia, the question is not whether candidates oppose abortion, but how to quantify how much they oppose it. Cain and Collins adhere to the one-exception rule, opposing abortion except when the health of the woman is in jeopardy. They pound Isakson for being a three-exception man, who also does not oppose abortions in cases of rape and incest. Cain's attacks are delivered in the crisp style of a man who charges $25,000 per appearance to give motivational speeches and is the author of several can-do business books with titles such as "CEO of Self."

"People say I'm Reaganesque," he offers.

Isakson is not Cain's only target when it comes to abortion. Cain rattles off statistics about high rates of abortion in the black population and high percentages of abortion clinics in predominantly African American neighborhoods. In an interview on his campaign bus, Cain said he considers "plausible" a theory that the abortion rights group, Planned Parenthood, was formed to systematically lower the black population. "One of the motivations was killing black babies," he said, "because they didn't want to deal with the problems of illiteracy and poverty."

Abortion is the thorniest of issues for Isakson, a three-term congressman who has spent 26 of the past 28 years in elected or appointed offices. He was considered a good bet to win the Senate nomination in 1996 until he aired a television commercial, with his wife and daughter, saying he opposed a constitutional amendment banning abortion and trusted Georgia women "to make the right choices."

"It had a huge impact," said Jerry Keen, a Republican Georgia House member from St. Simons Island and former chairman of the state's Christian Coalition. "Without that, he would have won that race."

In this summer's race, Cain is hoping to keep Isakson below 50 percent of the vote and force a runoff. Cain and Collins, whose campaign has suffered from sluggish fundraising, have accused Isakson of casting 14 "pro-choice" votes, including supporting a measure to allow privately funded abortions on U.S. military bases abroad. Cain sometimes leads into his abortion critiques of Isakson by telling listeners that there are major differences between them, "and I'm not just talking about the color of our eyes."

Isakson, an understated campaigner in contrast to the charismatic Cain, has responded by saying that he "respects life." His Web site lists a string of antiabortion credentials, from sponsoring legislation to suspend distribution of the RU-486 abortion pill to presiding over the final debate on the Partial Birth Abortion Ban Act.

Facing a persistent challenger, Isakson and his staff have tried to label Cain an outsider because he left Georgia after college and lived for many years in Omaha while running Godfather's. Cain, worth $5 million to $10 million, lives in a home that he bought five years ago outside Atlanta.

It was a return to the city where Cain attended segregated schools and where his father was a chauffeur for the chief executive officer of Coca-Cola Co. After segregation, Cain said he decided not to be an activist: "I walked into all-white corporate environments. . . . A few of us ran through that door and never looked back."

Both Cain and Isakson have sought to identify themselves with icons of conservatives in Georgia: President Bush and Zell Miller, the retiring Democratic senator from Georgia whose support of Republican policies and criticisms of the Democratic Party have made him a darling of the right.

The political novice hitting all the right notes in the Senate campaign is learning subtle lessons from the Miller playbook. Cain's campaign bus was stocked with peanuts packed in New Jersey, a bit of a symbolic faux pas on a tour of Georgia peanut country. But a Miller staffer climbed on board in Valdosta carrying a present with indisputable local appeal: packs of individually wrapped snacks labeled in big, bold letters: "Georgia Peanuts."

Georgia Republican Herman Cain is bidding to be the first African American elected to the U.S. Senate from the Deep South since Reconstruction.