FILE - In this Oct. 11, 2012 file photo, Sen. Dean Heller, R-Nev., left, and Rep. Shelley Berkley, D-Nev., right, wait for the start of their senate debate with moderator Mitch Fox, cen

 

              FILE - In this Oct. 11, 2012 file photo, Sen. Dean Heller, R-Nev., left, and Rep. Shelley Berkley, D-Nev., right, wait for the start of their senate debate with moderator Mitch Fox, cen
FILE - In this Oct. 11, 2012 file photo, Sen. Dean Heller, R-Nev., left, and Rep. Shelley Berkley, D-Nev., right, wait for the start of their senate debate with moderator Mitch Fox, center, in Las Vegas. The party that runs the Senate next year may be decided by how well President Barack Obama and Mitt Romney do in toss-up states like Nevada, where ballots features parallel Senate races about as races about as tight as the presidential contest. (AP Photo/Julie Jacobson, File)