Most Doubt a Resolve to Change Campaign Financing, Poll Finds
New York Times/CBS News Poll finds most Americans doubt Pres Clinton and Congress are sincerely committed to changing campaign financing system, even though significant majority believe fundamental changes are needed; finds Clinton is maintaining strong personal standing with public, despite months of sometimes withering accusations of improper campaign and fund-raising tactics, but that Vice Pres Al Gore has suffered sizeable loss of support as controversy has grown; charts (M)