Presidential race buffets Senate battle

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. (AP Photo/Julie Jacobson, File)

WASHINGTON (AP) — 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, Ohio, Virginia and Wisconsin, where ballots feature parallel Senate races about as tight as the presidential contest.

The mammoth campaign organizations built by Obama and Romney, his Republican challenger, are focusing their voter registration and turnout efforts in those four states and a handful of other presidential battlegrounds. Congressional candidates there are latching onto the help that can come from the larger, better-funded presidential campaigns.