NEW : Meanwhile , going over the cliff gives Obama more leverage , `` because then all of sudden , middle-class people 's taxes are going to rise , and that 's going to be bad for every politician in Washington . '' McConnell and Biden are main negotiators now , sources on both sides say . Comment: Obama calls on GOP to cut a deal on taxes ; Republicans argue Obama is overspending .
NEW : McConnell and Biden are main negotiators now , sources on both sides say . Comment: Obama calls on GOP to cut a deal on taxes ; Republicans argue Obama is overspending .