Richard M. Daley, sworn in to a third term as Cook County state's attorney just last week, was poised Monday to renew his quest for the mayoralty of the nation's third largest city, which his father ruled for 21 years.

Daley scheduled a Monday morning news conference at which he was expected to announce his intention to enter the Feb. 28 Democratic special primary election for mayor.That would make Daley the seventh announced Democrat and the eighth candidate to declare for the special elections to be held next year to fill the unexpired term of the late Mayor Harold Washington.

Daley, 46, son of the legendary Chicago "boss," Mayor Richard J. Daley, already is considered the frontrunner, on the basis of early public opinion samplings and due to his strong showing last month in his re-election as the county's top prosecutor.