A Democratic Party challenge to the makeup of the City Council under the District of Columbia home rule charter was rejected yesterday by the U.S. Supreme Court.

Splitting 6 to 3, the court affirmed a U.S. District Court ruling last March upholding the charter's limit on the number of at-large seats any one political party may hold.

The charter limits any political party to two of the four at-large seats. The Democratic Central Committee and party leaders claimed that under "one-person, one-vote" principles they should have a chance to run for, and win, all four seats. Democrats, with 77 per cent of the District's registered voters, hold 11 of 13 council seats.

Yesterday's high court action was announced without an opinion but after the Justice Department, at the court's request, filed a brief in the case.

Solicitor General Robert H. Bork defended the charter, relying in part on the unique character of the city's relationship to Congress. "In giving a voice to those who belong to minority parties or are independent of any party," he said, "Congress has apparently sought to avoid neglect of their legitimate interests and to facilitate a harmonious working relationship among the council, Congress and the presidency."

The Democrats got the votes of three court members appointed by Republican President Richard M. Nixon - Chief Justice Warren E. Burger and Justices Harry A. Blackmun and Lewis F. Powell Jr. - who said they considered the case worthy of a full hearing and a written decision. However, four votes are required for full high court review.