Illinois Republican Lynn Martin was sworn in Friday as secretary of labor and President Bush said she would become "a powerful force for good" in the American workplace.

"I know that Lynn Martin is also committed to reaching out to America's workers," Bush told hundreds of Labor Department officials and Republicans who turned out for the ceremony.Mrs. Martin, 51, a former congresswoman from Rockford, Ill., promised to do "the best job I know how" and thanked Bush in warm terms for naming her to his Cabinet after her loss in last fall's Senate race against Democrat Paul Simon.

"You have my friendship because you're a doggone good friend, and I'm sure glad you're mine," she declared.

"I also want to thank Paul Simon, without whose help I would not be here," Mrs. Martin cracked. The breezy one-time school teacher also noted that protocol now places her ahead of her husband, federal Judge Harry Leinenweber of Chicago, who administered the oath.

"But he says that he has a lifetime appointment," she added.

"You have my commitment as to the Department of Labor and the working men and women of America to do the best job I know how," she told Bush.

Bush mentioned the growing number of people from Illinois in his

Cabinet, including Transportation Secretary Samuel Skinner and Agriculture Secretary-designate, Edward R. Madigan, a former congressman.

"It's getting to be a cabal," Bush said. He did not mention Veterans Affairs Secretary Edward Derwinski, another former Republican congressman from Illinois.