With Senate Majority Leader Howard H. Baker Jr. (Tenn.) predicting yesterday that Ernest W. Lefever can win a close vote for confirmation to be the Reagan administration's principal human rights advisers, the battle over the controversial nominee appears headed for the Senate floor.

In an apparently related move, Baker said the nominations of two other candidates for high-level State Department jobs that have been blocked by Sen. Jesse Helms (R-N.C.) will move forward soon.

Baker said that the nominations of Chester A. Crocker to be assistant secretary for African affairs and Myer Rashish to be undersecretary for economic affairs will be acted on late this week or "certainly next week."

Helms, a strong supporter of Lefever, told reporters after a meeting with President Reagan at the White House that Crocker and Rashish would be approved, but did not indicate when or whether he would get the deal he had been trying to strike in return for letting Crocker be confirmed.

Helms had asked the State Department to name Clifford A. Kiracofe, 32, Crocker's chief assistant for U.S. policy toward southern Africa in exchange for Helms lifting his objection to Crocker.

Kiracofe was at the State Department for an interview with Crocker yesterday, but the department issued a strong statement saying the executive department has the sole prerogative to name officials at that level. State Department sources said that no deals have been made with Helms and that Kiracofe is unlikely to get the job.

The Senate Foreign Relations Committee will question Lefever again today, but Republican and Democratic sources said that enthusiasm for additional hearings has waned and that the committee is expected to vote Friday and send the nomination to the Senate floor with a recommendation of disapproval.

"I think we can win. It will be difficult, but it's winnable," said Baker, who is counting votes in the Senate.

Reagan and senior White House aides have thrown their full support behind Lefever. "This is an excellent man," said White House counselor Edwin Meese III, who had his first lengthy meeting with Lefever Tuesday. "I was tremendously impressed by sitting down and talking with him."

Meese suggested that as part of the effort to wn Senate confirmation for Lefever, the White House would arrange meetings between Lefever and individual senators to help correct what Meese called "misstatements" and "unfair innuendoes" that have arisen during the confirmation hearings.

All eight Democratic members of the committee plus Republican Sens. Rudy Boschwitz (Minn.) and Larry Pressler (S.D.) planned yesterday to vote against Lefever. Committee Chairman Charles H. Percy (Ill.) was said to be leaning toward opposing the nominee.

Pressler said he would cast his negative vote reluctantly. "This vote puts Republicans in a very difficult position," he added, making it clear that he would have preferred to see the nomination withdrawn.

"The Republican Party traditionally has been on the wrong side of the civil rights-civil libertarian issues," Pressler said. "A vote by a Republican Senate for Lefever would kind of put us on the side of not being sensitive to civil rights."

Lefever, whose opponents criticize him for saying he would be more tolerant of human rights abuses in nations friendly to the United States than in hostile countries and for his public policy center's connection with the Nestle Corp., was embroiled in a new controversy yesterday when one of his brothers said Lefever believes that Blacks are intellectually inferior to whites.

Deputy White House press secretary Larry Speakes said Lefever denied the charge to State Department officials. "He has not said this, nor does he believe it," Speakes said.

The nominee's brother, John, backed by a second brother, Donald, told the Associated Press that the nominee made the statement about seven years ago in family conversations.

Meese told reporters that administration officials had suggested that Lefever not make any public appearances while the fight for his confirmation is under way. One of the results was that Lefever canceled his scheduled speech to the Council of the Americas meeting yesterday.