The Democratic takeover of the White House hasn't ended the legal woes of House Ways & Means Committee Chairman Dan Rostenkowski (D-Ill.). The Justice Dept. is continuing a criminal probe of alleged irregularities in Rostenkowski's financial dealings with the House post office. Should Rosty be indicted, Sam M. Gibbons (D-Fla.) would become acting chairman pending trial. But should Rostenkowski be forced out of office, the Democratic Caucus would likely pass over Gibbons, 73, and closely tied to business lobbyists, and turn instead to Charles B. Rangel (D-N.Y.) as a permanent replacement.