COLUMBIA -- After Oprah Winfrey's Sunday visit to Columbia, Democratic presidential hopeful Barack Obama will be left to one of two fates:
1. He'll gain a leg up among S.C. women voters, perhaps catapulting ahead of front-runner U.S. Sen. Hillary Clinton.
2. Her endorsement will have little impact, proving once and for all that star endorsements don't translate into female votes even when the endorser is one of the nation's most influential and popular figures.
"Oprah's endorsement certainly can't hurt him," said Jack Bass, a political scientist at the College of Charleston. "But we don't know if it will help him, either. We've never seen a situation like this before. It'll be the first real test of whether you can transfer votes."
Celebrity endorsements are nothing new during election season. Sen. Hillary Clinton's husband, Bill Clinton, and singer/actress Barbra Streisand are on the campaign trail for the front-runner.
Pro wrestler Ric Flair and martial arts star Chuck Norris are backing Mike Huckabee. John Edwards is appearing with singer/actor Harry Belafonte.
But Winfrey, a billionaire who has maintained her Everywoman appeal, might be different.
"There are few people out there who have her kind of star power," Bass said.
Obama's campaign hopes to rally Winfrey's women supporters and bring others into his fold who don't ordinarily care about politics.
Oprah fan Kim Swartz of Irmo thinks the strategy will work.
"She'll be able to sway a percentage of voters," said Swartz, who will attend Sunday's rally. "Particularly those who aren't paying attention to politics. And she'll encourage a lot of people to get out and vote who don't usually vote."
But Swartz said women such as herself who are paying attention to politics won't be swayed to base their vote on anything other than the issues.
"I'm leaning toward Mitt Romney," Swartz said, noting the only Democrat she would be apt to vote for would be Winfrey herself.
"She empowers women. She motivates us and lets us believe that we can overcome all obstacles," Swartz said. "She is definitely a symbol of achievement."
Black women could decide S.C. race
The female vote is a key bloc for Obama and all other candidates. Women are expected to cast more than half the votes in January's primary. African-American women potentially could decide the race, political analysts have said.
Polling shows Obama's message is resonating more with male African-American voters in the state, who favor him over the other Democratic candidates.
But Obama continues to struggle with U.S. Sen. Hillary Clinton, D-N.Y., to be the favorite of female voters.
That's where Winfrey comes into play.
• Of her daytime audience of 8.6 million viewers, 75 percent are women, according to Nielsen Media Research.
• More than half of her viewers are older than 50, according to Nielsen. Research shows older women are more likely to vote than younger ones.
• Similarities exist between those who watch Oprah and those in South Carolina who say they'll vote for Obama. Many members of both groups are in their 40s and 50s, earn $50,000 or less and are married.
The question is whether Winfrey can convince her fans to go to the polls for Obama.
"The fact that there is overlap is important because it shows he can make inroads with the demographic that comprises Oprah viewers," said Scott Huffmon, a political scientist at Winthrop University who created a rough profile of Obama's supporters in South Carolina for The State newspaper.
"It is also to his benefit that there isn't perfect overlap," Huffmon said. "After all, what good would it be if they were preaching to the choir? The fact that her viewership isn't already fully in his camp means there are more fish in that sea."