An hour-long meeting among 10 Republican senators and national black leaders yesterday drew a prediction by Clarence Mitchell of the National Association People that if the proposed constitutional amendment to give District residents full voting representation in Congress gets to the floor of the Senate this year, it will "result in certain victory."

Mitchell and other proponents of the amendment, which passed the House earlier this year, said they came away from the meeting assured that Sen. Howard Baker (R-Tenn.), the Senate minority leader, would not attempt to block the resolution from getting to the floor. They also said they were optimistic that Baker would support it if it came to a vote.

The Rev. Jesse Jackson said that two senators who attended the meeting in Baker's office "started off not inclined" to favor the proposition, but later exhibited "openness" that he interpreted as "a step in the right direction."

Jackson said he detected a change in attitude by Senators John Tower of Texas and Henry Bellmon of Oklahoma. None of the senators who attended, who also included John Danforth of Michigan, Peter Domenici of New Mexico, Ted Stevens of Alaska, Richard Lugar of Indiana, s.I. Hayakawa of California, Robert Griffin of Michigan and Milton Young to North Dakota, flatly opposed the proposal, Jackson said.

The District's nonvoting delegate to the House, Walter E. Fauntroy, said a similar delegation of black leaders hopes to meet next week with Sen. Robert C. Byrd (D-W. Va), the Senate majority leader.

Mitchell said supporters decided last week to meet with the Republican leadership before going to Byrd because "there is no way to get this passed without bipartisan support." He said Baker promised to tell Byrd that he is "disposed to cooperate."

Passage of the resolution, and its subsequent approval by the legislatures of three-fourths of the states, would have "a tremendous impact around the world," said Mitchell, head of the NAACP's Washington bureau.

Jackson said that Tower remarked that he had supported black issues in the past but the black voters had not reciprocated at the polls. Jackson said he told Tower "it was the Republican Party that deserted blacks, not the other way around," citing the presidential candidacy fo Sen. Barry Goldwater (R-Ariz.) and what he called the "benign neglect" policy in the Nixon Administration. Goldwater announced earlier this year, that he would vote for the resolution.

Jackson said Republican senators who have supported the cause of blacks consistently, such as Jacob Javits of New York, Charles Percy of Illinois and Charles McC. Mathias of Maryland "have gotten our votes,"

An aide said that Baker had not made a decision. Baker is likely to announce his position after the blacks meet with Byrd, the aide added.

Also attending the meeting were M. Carl Holman, president of the National Urban Coalition; Berkley Burrell, president of the National Business League, and D.C. Council Chairman Sterling Tucker, who also is president of Self-Determination for D.C., the lobbying organization that is advocating passage of the resolution.