Ailing Alabama Gov. George C. Wallace, 66, kept his state guessing yesterday whether he would seek an unprecedented fifth term, even as his longtime press aide, Billy Joe Camp, jumped ship to join a crowded field of would-be Democratic successors.

Wallace called one of his infrequent news conferences at the state capitol in Montgomery yesterday afternoon amid speculation that Camp's announcement meant Wallace would not seek reelection this year to the office he has held, on and off, since 1963.

Instead, Wallace said: "I'm able to run for governor. I am able to be governor again . . . . But I'm not sure. I haven't decided yet."

Wallace, who has been hospitalized seven times since winning a fourth term in 1982, promised he would make up his mind and disclose his plans within a month.

Camp, 47, Wallace's press secretary in three administrations dating to 1971, announced earlier in the day that he would resign from Wallace's office Friday to begin a statewide campaign. "If I am going to do this, I can't wait any longer," he said.

Wallace had surgery last summer to relieve some of the pain from the 1972 assassination attempt that has confined him to a wheelchair, and though it enabled him to lead a trade mission to China last fall, he has been barely visible through most of his term in office.

His health makes him politically vulnerable, according to a series of polls taken in the past year. A Birmingham Post-Herald poll last fall showed that, by 51 to 31 percent, Alabamians think the most important decisions in state government are being made by Wallace's staff, not the governor; and that 59 percent of the voters are less likely to vote for him for reelection because of concerns about his health.

Former state party chairman James Knight said Wallace told him months ago that he "won't go out a beaten man," and has resolved to step down if he becomes convinced he cannot win a fifth term.

"Camp's getting in sure makes it look like Wallace won't run," added Democratic National Committeman Richard Hartley, in a view widely shared among leading state Democrats.

Wallace, who rode to national prominence in the 1960s with a vow of "segregation now, segregation tomorrow, segregation forever," won 10 million votes as a third-party presidential candidate in 1968, and had won four Democratic presidential primaries in 1972 when his campaign was cut short by an assassination attempt that left his legs paralyzed.

In 1982, he was elected to a fourth term as governor with heavy black support, after running as a self-described reformed segregationist.

With or without Wallace, the Democratic primary promises to be a free-for-all. In addition to Camp, the announced candidates are Lt. Gov. William Baxley, generally regarded as the front-runner; former lieutenant governor George McMillan, a progressive with appeal in urban areas; Attorney General Charles Graddick, and former governor Fob James.