Democrats and Republicans alike are fretting over what might go seriously wrong before, during -- or just after -- the Nov. 6 presidential election.
Both parties have amassed lawyers and volunteers to watch polling places and appeal to local election officials if problems arise.
Campaign officials say it's possible that one candidate could win the popular vote but lose the all-important Electoral College tally. That's what happened in 2000 when George W. Bush defeated Al Gore after a contentious recount in Florida.
Perhaps the most nightmarish result next month would be a 269-269 Electoral College tie between President Barack Obama and Republican Mitt Romney. That result is unlikely but far from impossible.
The U.S. House would choose the next president in such a case.