A team of observers sponsored by the American Conservative Union reported yesterday that in its opinion the recent elections in Rhodesia were "free and fair."

Rep. Robert E. Bauman (R-Md.), chairman of the ACU, said he was introducing legislation in the House calling for the lifting of economic sanctions against Rhodesia on the basis of the election results.

The ACU's observer team consisted of M. Stanton Evans, a radio commentator; Byron Engle, former public safety director of the U.S. Agency for International Development, former representative Howard Pollock, and Smith Hempstone, a syndicated collumnist.

After traveling thousands of miles in Rhodesia during the election and after interviews with numerous voters, they said the balloting was remarkbly free for a country in a civil war. Members of the observer team at a press conference yesterday cited reports by American journalists in Rhodesia to support their conclusion.

Evans, chairman of the observer team, said he had been impressed by the racial harmony in Rhodesia. "There 's no feeling of racial hostility," there, he said.

In the Senate, Harry F. Byrd (Ind.-Va.) said President Carter himself should move swiftly to lift the sanctions and "to cease listening to the extremists and the zealots who dominate State Department thinking in regard to southern Africa."

At a meeting Monday with his senior advisers, however, Carter reportedly decided to support congressional liberals hoping to block immediate lifting of sanctions.

Republican National Committee Chairman Bill Brock echoed the calls from conservatives on Capitol Hill for action now.

"The people of Rhodesia have participated in their first free election, despite threats, acts of overt terrorism and in the face of clear opposition of a large percentage of the world's governments, including the United States," Brock said. "The next step is up to the Carter administration."