Presidential press secretary Jody Powell, whose stock in trade is keeping the news media satisfied, will travel to South Carolina on Friday the 13th to help raise campaign funds for a journalist-turned-candidate, Jack Bass.

Bass an expert on suthern politics who coauthored a highly acclaimed a hard-hitting campaign for Congress that appears to be gaining momentum.

Given virtually no chance a few months ago to unseat conservative Republican Rep. Floyd Spence, Democrat Bass is pressing the incumbent increasingly hard and is given an outside chance of an upset.

"I've known Jody for several years, and he said he'd be happy to help," said the 43-year-old Bass. "The White House now perceives this as a winning race."

Spence, is 50, a genial, popular backslapper nicknamed the "kissing congressman" in his district, a seven-county area in the center of South Carolina that includes the capital city of Columbia. Ranking Republican on the House committee that investigated the Korean influence-buying scandal in Congress, Spence won his fourth two-year term in 1976 with 58 percent of the vote.

A determined Bass has "declared war" on Spence's voting record, calling the incumbent "too negative" and "out of step" with the rest of the state's delegation.

Bass says that his book, "The Transformation of Southern Politics," proved that the political climate in the South "has changed tremendously in the past eight years, but Floyd Spence hasn't. He is an anachronism."

To win the Democratic nomination, the aware-winning political reporter trimmed his hair, shaved off his beard and took elocution lessons. After winning a hard-fought Democratic primary, Bass immediately went on the attack against Spence, blasting him for voting "against the interests of senior citizens, consumers and taxpayers."

Bass press releases - many of which he writes himself - feature catchy phrases that turn into easy headlines. The Kemp-Roth tax cut bill, which Bass opposes as inflationary, is labeled "snake oil" and a "Republican shell game designed to fool middle and lower income taxpayers."

Of Spence's vote to continue the oil depletion allowance, Bass says it's a "$2 billion a year subsidy to the oil industry, and there aren't any oil wells in the 2nd Congressional District."

Continually put on the defensive, Spence tried for a while to label Bass' attacks on his voting record as "name-calling." Lately, Spence has remained in Washington except on weekends, saying little. Now Bass challenges him to "come out of hiding in Washington."

Bass, a former reporter for the Charlotte (N.C.) Observer, says he will put together a coalition of blacks, senior citizens, consumers, environmentalists, and education and labor groups all unhappy with Spence's voting record. Spence has the most conservative record of South Carolina's six House members.