An apparent misunderstanding drove Richland County Democrat Kit Smith to a last-minute challenge of longtime Republican Sen. John Courson, setting up a race that had Republicans and Democrats buzzing Wednesday.

The race has political junkies talking because it pits Smith, a love-her-or-hate-her county councilwoman, against Courson, a well-liked senator who has traditionally garnered support from both parties.

And the candidates have known each other for more than 25 years. Smith and Courson’s wife, Lisa, were Delta Delta Delta sorority sisters at USC, although Smith is a few years older. Smith taught Courson’s children Sunday school at Trinity Episcopal Cathedral.

Both live in Shandon — Smith on Edisto, Courson on Wheat.

“We will be in for a donnybrook, I would suspect,” said Crawford Cook, a political consultant who is personal friends with both Smith and Courson. “This will be perplexing.”

Smith said she began getting phone calls from supporters last week asking her to run.

But by Monday morning, Smith and her husband, Joel, dean of USC’s business school, had decided the timing wasn’t right. Running would mean forgoing her monthlong August retreat at her mountain house, and cutting into the festivities surrounding her son’s September wedding and time with her parents, who live in Gaffney.

It’s also a potentially crucial time for Richland County’s Town and Country land use plan, an effort Smith has championed. The council on Tuesday delayed a key vote until June.

Later Monday, someone told Smith that Courson had not yet filed. She said she and her husband decided if no one had filed by Tuesday morning, the last day of filing, she would.

Still believing Courson had not filed, she turned in her papers. Tuesday. “Then, I found out that John did file.”

Republican party records indicate that Courson’s papers were filed at 4 p.m. on March 16, the day filing opened. His filing was reported in The State the next day.

But Smith said the circumstances don’t matter.

“What ultimately motivated me to file is I think the General Assembly has been making irresponsible decisions,” she said. “I am very concerned about the shell game they are playing of blaming local government. A large part of the property tax increase that people have seen should be laid squarely at the doors of the General Assembly.”

Republican Party leaders say Smith made a bad decision.

House Majority Leader Rick Quinn, R-Richland, said voters are happy with Courson, and he was surprised Smith would challenge him.

“I think John is an exceptional senator and once people start thinking about, ‘Should we remove John Courson?’, the answer is going to be, ‘No.’”

Courson, a senator since 1985, said he wasn’t surprised he had opposition. He’s been opposed in all but one of his races, most recently by Richland County Council member Tony Mizzell.

But Courson said he was surprised to learn that his opponent would be Smith. (Neither has opposition in the June primary.)

Courson acknowledged that he and Smith have many mutual friends.

“I am sure there will be divided loyalties as this thing evolves,” he said. “But that’s politics.”

Former Gov. Jim Hodges, who lives near both candidates, predicted the race will be a “real barnburner.”

“You’ve got two people who are well-known, well-respected. Both have the capacity to raise a lot of money,” said Hodges.

Hodges said he, like others, had always heard talk that Smith might one day seek that Senate seat. But he said he hadn’t expected it now.

Courson said that he’s been successful against Democrats in the past because he has put together coalitions that are “fairly unusual for a Republican.”

But this time, he said, that may not be necessary because the district lines were changed in 2002, pushing the district partly into Lexington County, which is strongly Republican.

Smith, who doesn’t have to give up her County Council seat, said she doesn’t expect the campaign to be easy.

She said she called Courson Tuesday after she filed and left a message on his voice mail.

“This is not personal. It’s policy issues,” she said.

The last-minute decision may seem uncharacteristic for Smith, a self-described “policy wonk” who is known for researching issues and formulating strategies.

But she said she’s also passionate. “I think it was the passion that took me there yesterday,” she said.

Reach Hill at (803) 771-8462 or sehill@thestate.com