H.M. (Mickey) Michaux, who won a plurality in last Tuesday's Democratic primary, is getting a lot of attention in his effort to become North Carolina's first black congressman this century. Michaux, a Durham County lawyer and U.S. district attorney in the Carter administration, polled 44.1 percent of the vote to 32.9 percent for I.T. Valentine Jr., a former state legislator and Democratic state chairman, and 25 percent for former state house speaker James Ramsey. Because he didn't win a majority, Michaux and Valentine will meet in a runoff July 27 and political observers think Valentine has the advantage. The district is a redrawn version of the one represented for the past 30 years by Democrat L.H. Fountain, who decided to retire after Durham County, which has a large and politically active black population, was added.

Still, about 65 percent of the voters in the new district are white and observers think Michaux, who campaigned for white votes, may have gotten all the support he can. The state AFL--CIO is raising money for Michaux, who was the most liberal candidate in the primary. Valentine, the most conservative, has tbe backing of business political action committees and the endorsement of the U.S. Chamber of Commerce.