ATHENS (Reuters) - The radical Greek leftist party Syriza extended its poll lead over the co-ruling conservatives to 6.5 points in a survey published on Monday, ahead of a snap election on Jan. 25. The University of Macedonia survey for Greece's SKAI television indicated that Syriza, which wants to renegotiate a chunk of Greek debt and end austerity measures, would win 33.5 percent of the vote ...