Washington -- Rep. Pete Stark, D-Fremont, pounced Monday on the ethical troubles of a fellow House member, Republican Randy "Duke'' Cunningham of San Diego County, who is under investigation for an alleged sweetheart real estate deal with a defense industry lobbyist. "Attention Powerful Lobbyists,'' read the headline in a satirical advertisement Stark bought Monday in the online editions of CongressDaily and the Hotline, a political roundup. "House for sale by influential member of Congress." A San Diego federal grand jury and the FBI are investigating Cunningham, who sits on the House defense appropriations subcommittee, for his sale of a home...