President Reagan's nominee as general counsel of the Equal Employment Opportunity Commission acknowledged yesterday that he privately suggested that blacks and women can overcome discrimination by offering to work for lower wages than white employes.

Jeffrey I. Zuckerman said on the second day of his Senate confirmation hearings that he was citing studies by conservative black economist Thomas Sowell and another professor. Nevertheless, he said, he fully supports the federal Equal Pay Act for minorities and women.

Sen. Edward M. Kennedy (D-Mass.) led a Democratic assault on the nomination in the Labor and Human Resources Committee, which agreed to call Zuckerman a third time for testimony. The contentious session carried echoes of the Democrats' successful fight to block a promotion for Assistant Attorney General William Bradford Reynolds, whose civil rights views were forcefully espoused by Zuckerman yesterday.

Zuckerman, 35, a former Justice Department official, has been chief of staff to EEOC Chairman Clarence Thomas for 18 months. Kennedy frequently chided Zuckerman for evading questions and said the nominee appeared to oppose personally several laws against age and sex discrimination.

Referring to Zuckerman's meetings with EEOC staffers, Kennedy said, "You argued that the Equal Pay Act hurt blacks in South Africa and the American South because white employers would be willing to hire blacks if they could pay them less . . . . You argued that women were in a similar situation and that employers would be more willing to hire them if they could pay them less than white men."

Citing a 1985 draft report, Kennedy said, Zuckerman wrote that the free market will punish discrimination "only if members of the disfavored group are able to offer their labor for less than members of the favored group earn."

Kennedy said the EEOC staffers believed "that the case was being made . . . that the way we're going to get [women] employed is by paying them less."

Zuckerman said he was citing academic studies of market conditions before 1960s civil rights laws that guaranteed equal pay for women. "I agree with that principle 100 percent," he said.

"Why the devil did you raise this argument in 1984?" Kennedy replied. Zuckerman did not answer.

Democrats need at least two Republican votes to reject Zuckerman, and while committee Chairman Orrin G. Hatch (R-Utah) strongly defended the nominee, other GOP members were critical.