The White House is sending out talking points on Miers in which they point out:

10 out of the 34 Justices appointed since 1933, including the late Chief Justice William Rehnquist and the late Justice Byron White, were appointed from positions within the President’s Administration. The late Chief Justice William Rehnquist was appointed in 1971 from his position as Assistant Attorney General. The late Justice Byron White was appointed in 1962 from his position as Deputy Attorney General. Neither had prior judicial experience.