Senator Joseph I. Lieberman, the Democrat-turned-independent from Connecticut, was allowed to keep his chairmanship of the Homeland Security and Governmental Affairs Committee on Tuesday despite his support for Senator John McCain in the presidential campaign. Democratic senators voted instead to oust Mr. Lieberman from the Environment and Public Works Committee, where he had been chairman of a subcommittee. That penalty was a slap on the wrist compared with the prospect of losing the homeland security leadership post.








