FILE - In this Oct. 31, 2008 file image released by CBS, CBS News anchor Katie Couric rehearses for Election Night of Presidential Campaign 2008 in New York. After losing viewers to cable news networks on recent election nights, television's biggest broadcasters are fighting back hard for the midterm contest. ABC, CBS and PBS will each stream part of their election-night coverage on the Web on Tuesday, and NBC plans six hours of results lasting into early Wednesday morning. (AP Photo/CBS, John P. Filo, FIle) ** MANDATORY CREDIT; NO SALES; NO ARCHIVE; NORTH AMERICA USE ONLY **