(CNN) - The Republican presidential field appears to face a tough general election fight in a CNN/Opinion Research Corp. poll released Saturday.

According to the survey, both of the Democratic front-runners, Sens. Hillary Clinton of New York and Barack Obama of Illinois, hold mostly double-digit -- and statistically identical -- advantages over Republican presidential candidates Mitt Romney, Rudy Giuliani and Mike Huckabee, drawing greater than 50 percent support in each hypothetical matchup. Read More