KEY POINTS:
Republican presidential rivals Rudy Giuliani and Mitt Romney scornfully debated immigration in a provocative, no-holds-barred CNN/YouTube debate just over a month before the first votes are cast.
Giuliani, ahead in national polls, accused Romney of employing illegal immigrants at his home and running a "sanctuary mansion".
The confrontation came at the start of a CNN-YouTube debate that forced the candidates to confront immigration, signalling the volatility of the issue among Republican voters.
The eight Republican candidates fielded questions including abortion, gun control and farm subsidies.
The candidates tried to position themselves to the right of each other, knowing that conservatives hold sway in nominee selection.
- AP
