Pro-Republican Groups Prepare Big Push at End of Races

The anonymously financed conservative groups that have played such a crucial role this campaign year are starting a carefully coordinated final push to deliver control of Congress to Republicans, shifting money among some 80 House races they are monitoring day by day.

Officials involved in the effort over the midterm elections' final week say it is being spearheaded by a core subset of the largest outside conservative groups, which have millions of dollars left to spend on television advertisements, mailings and phone calls for five potentially decisive Senate races, as well as the scores of House races. Bolstered by a surge in last-minute donations and other financial support, outside liberal groups and unions say they are stepping up their response in advertising and get-out-the-vote efforts, but remain largely outgunned by the scale and sophistication of the operation supporting Republican candidates.