COLUMBIA, South Carolina (AP) — With South Carolina’s sordid history of dirty politics, it’s no wonder conspiracy theories abound about an unknown, unemployed military veteran winning the Democratic nomination for U.S. Senate.

This is, after all, the birthplace of political maestro Lee Atwater and where rumors of an illegitimate black child ruined John McCain’s 2000 presidential run.

Perhaps the most surprising element of Alvin Greene’s victory so far is that nothing yet sufficiently explains how it happened.

Greene stunned the state with his win Tuesday over a four-term former lawmaker considered the presumptive Democratic nominee. The 32-year-old candidate who lives with his father and faces a felony charge will challenge Republican juggernaut U.S. Sen. Jim DeMint in the fall.

WATCH ‘TODAY SHOW’ COVERAGE OF ALVIN GREENE HERE:

Visit msnbc.com for breaking news, world news, and news about the economy

The week has seen Greene change from sweat pants and a T-shirt to dark suit and tie, but he’s still stammering his way through interviews as he did before the election when he repeated several vague phrases about job creation to an Associated Press reporter and declined to talk about where he campaigned.

“Last weekend, was the first, I mean, I had friends and their friends’ help,” Greene said Wednesday, pausing several seconds. “I mean, I don’t want to talk about the campaign. We get caught up in the campaign — ‘How he won?’ — whatever. I worked hard.”

The result stumped Greene’s opponent, Vic Rawl, who has accepted the help of a couple of mathematics professors who found some possible anomalies in voting patterns. Another expert examined voting machines used in the primary to check for malfunctions or tampering. The campaign promised to release any information gathered by the experts and their conclusions.

When The Associated Press broke word of the felony charge that day, the stunned Democratic establishment lashed out with a panoply of suspicions over how Greene could have paid his $10,440 filing fee and won. House Majority Whip Jim Clyburn wants authorities to investigate. “Something is amiss,” he said.

While it’s tough to explain how Greene came up with the cash (he says he saved up for two years), the conspiracy theories posed by analysts and Democrats are not ironclad:

— Is Greene a shell candidate who got help from Republican forces seeking to discredit the Democratic Party? Greene says he hasn’t had help from anyone, save friends and family. State Republican officials call the allegation “absurd” and DeMint is considered a lock for a second term.

The state has open primaries, which means Republican voters could have chosen to vote in the Democratic primary and gone for Greene. But then crossover voters couldn’t have voted in a more-important four-way race for governor on the Republican ballot.

More than twice as many voters cast ballots in the GOP primary than in the Democratic contest, and vote totals show 19,000 voters selected a Democratic candidate for governor but skipped the U.S. Senate part of the ballot.

— Third-party help? Did Greene, who is black, get help from outside groups? A group that ran cable ads encouraging the unemployed to vote says it never promoted him and the director of the state’s NAACP chapter says he knew nothing about Greene before Tuesday night.

— Was Rawl a victim of the antiestablishment sentiment that swept the state’s primaries? Rawl carried few counties on Tuesday, but one of them was Charleston, where he serves on the county council.

Francis Marion University political scientist Neal Thigpen said he thinks Greene benefited from voters not knowing either candidate and choosing either a name that sounded familiar or the one at the top of the list.

“In this case, the guy got a lot of the blind vote,” Thigpen said. “It’s just a complete fluke.”

“The only mystery there to me is where the guy got the $10,000,” he added.

State Sen. Robert Ford, who came in third in his bid for the Democratic nomination for governor, said it is possible that black voters looking for a black candidate might have chosen Greene because of the spelling of his name.

“Voters didn’t know either candidate,” said Ford, who is black. “A lot of blacks who have the last name Greene add an ‘e’.”

Columbia lawyer Tom Turnipseed, a Democrat who openly discussed a past that included depression and electroshock therapy when he ran for U.S. House in 1980, is one state political veteran seldom surprised by South Carolina’s politics.

Atwater, who went on to advise Presidents Ronald Reagan and George H.W. Bush and lead the Republican National Committee, helped re-elect a Republican by joking about Turnipseed needing jumper cables to start his brain and engineering a push-poll on mental health.

Turnipseed said he doesn’t buy the conspiracy theories swirling around Greene’s victory.

“I’ve been trying to solve it,” he said. “It’s a wonderful thing to argue about. … Where did the votes come from? It couldn’t have been too many Republicans crossing over, they had such a hotly contested primary themselves.”

In a state where the contentious Republican primary for governor held voters rapt with infidelity allegations and racial slurs, the contest for the right to face DeMint simply fell to the backburner. U.S. Sen. Robert Menendez, who heads the group aimed at elected Democratic senators, says he’s not focusing resources on the state this year.

Ford also discounted conspiracy theories that blame Republicans for Greene’s victory, and says it doesn’t matter in the end.

“Ain’t nobody in this state can even think about beating DeMint,” Ford said.

___

Associated Press writers Page Ivey and Jeffrey Collins contributed to this report.

Copyright 2010 The Associated Press.