Blair Lee III was a professional politician in the more elevated sense of the term. What interested him was the way Maryland's turbulent democracy works, and he set about learning to know the state and its government with the same precision that a surgeon learns anatomy. Like a surgeon, his purpose was to make the thing work better. In 1977- 78 he served briefly as acting governor, and that is the tag usually attached to his name. But there was a great deal more to his long career than that.

He was born into one of Maryland's great political families and entered Montgomery County's Democratic politics at a time, shortly after World War II, when the party was fiercely divided between the old country-style machine and the increasingly well-organized suburbs. The enduring vice of Montgomery politics is an addiction to a narrow and zealous factionalism that was never worse than in those years. Mr. Lee's father, E. Brooke Lee, was the dominant figure in the old organization, while by age, education and outlook the younger Mr. Lee had much in common with the new wave of suburban voters who were determined to seize control. He chose to be a broker, valued by each side for his assured knowledge and his detached good judgment -- but that detachment always made him slightly suspect within the party. He retained that talent for detachment throughout his life; it protected his integrity, but it probably set a limit to his success in election campaigns.

He served in both houses of the General Assembly, then became lieutenant governor under Marvin Mandel and, after Mr. Mandel's conviction on charges of corruption, replaced him. The aura of scandal vanished from the governor's office under Mr. Lee, but whether because of the Mandel connection or his own cool and ironic manner, helost when he ran for a full term in his own right.

Among the many useful things that he accomplished for the state, the most important were in the field of education. Coming from the richest county in the state, he improved and strengthened the formula for distribution of state funds, limiting the disparity between the quality of schools in the most and least wealthy communities. It was a characteristically inconspicuous and important contribution to equality of opportunity. After leaving the governorship he served on the board of regents of the University of Maryland, and persuaded the General Assembly to set up the fund to augment the salaries of outstanding faculty there.

Maryland politics is a paradox. The most visible side of it has repeatedly been spectacularly tawdry, and yet the state is notably well run and provides fine schools for its children. If you are looking for an explanation, you might usefully begin by considering the career of Mr. Lee, who died last Friday at his home in Silver Spring.