US Democratic presidential front-runner Hillary Clinton has dominated news coverage of the 2008 White House race, partly due to negative segments about her on conservative talk radio, according to a new study released yesterday.

Clinton was the main subject of 17 percent of stories during the first five months of this year, almost twice as much coverage as the leading Republican candidate, Rudy Giuliani, who had 9 percent, the study found.

The tone of coverage for the two during that period was about equal - roughly 37 percent of stories were negative while 27 percent were positive, according to the study by the Project for Excellence in Journalism and Harvard University's Joan Shorenstein Center on the Press, Politics and Public Policy.