NEW YORK — Just over half of Americans believe Sen. Hillary Clinton is prepared to be the first female president of the United States, according to a new FOX News poll. In addition, Clinton is the preferred choice of Democratic voters for their party’s 2008 presidential nominee; on the Republican side, former NY Mayor Rudy Giuliani barely edges out Ariz. Sen. John McCain for frontrunner billing. Opinion Dynamics Corporation conducted the national telephone poll of 900 registered voters for FOX News from August 29 to August 30. The poll has a 3-point error margin. A slim 51-percent majority of voters...