Nov. 7 Nightmares: When Voting Goes Bad People wait in line for early voting in the parking lot of the Northland Park Center on Nov. 4, 2012 in Columbus, Ohio. As Americans count the hours until the election is over, thousands of lawyers for the Obama and Romney campaigns are preparing for the possibility that the counting of votes will stretch well beyond Tuesday night. Nine swing states hold the keys to victory in the race for the White House, and most polls have them within the margin of error, albeit with a distinct Obama edge. Many have mandatory recounts if the difference between the candidates is within a few percentage points (in most cases that amounts to several thousand votes). Come Wednesday morning there is currently an 8% chance, according to the New York Times" Nate Silver, that one of these states will hold up the determination of a winner in the presidential contest. If that happens, things will get ugly. All clean presidential elections are alike - whoever gets 270 electoral college votes becomes president. But each contested election is a misery all its own. In addition to the classic problems from past elections, like crowding, difficulty counting ballots and complaints of limited voter access, this year the expansion in early voting holds a new set of concerns. PHOTOS: The 2012 Presidential Election Year in Pictures Here are some of the different ways things could go wrong on Tuesday and what a battle in each state might look like. Ohio is the state of first concern, because it is the most likely decider - Silver gives it a 50% chance of being the difference-maker in the election. Already there are signs of problems. Jon Husted, the Ohio Secretary of State, mailed every one of Ohio's more than 7 million registered voters an absentee ballot application. Of the 1.4 million ballots that were sent out in response to applicants, most have been returned, but several hundred thousand haven't. That could mean a jump in provisional ballots on election day, as voters who received ballots by mail won't be allowed to cast binding ballots at the polling places. Provisional ballots from those voters, combined with the tens of thousands from voters who are challenged at the polls for improper ID, changed home addresses or other reasons, could become an issue. Ohio has already seen its share of legal wrangling, too. Husted fought to block early voting on the weekend before the election, but lost in the U.S. Supreme Court. Democrats, meanwhile, challenged a last-minute directive from Husted that would require election workers not to count provisional ballots if the voter didn't accurately fill out paperwork. Things may get even messier after the election. Ohio's board of elections will conduct a recount if the margin of victory is 0.25% or less, or in the range of 17,500 votes. Despite the state's well designed recount process, campaign lawyers are likely to challenge many votes if the margin is that close. The result of a hung vote in Ohio in a close race could be a lengthy delay in determining who becomes president. Ohio doesn't start counting provisional ballots until Nov. 17, and legal challenges could push it into December. The deadline for resolving electoral college disputes is Dec. 11. INTERACTIVE: 2012 Electoral College Calculator Map In Virginia, there are also potential ballot day problems. Obama and Romney are essentially tied in the latest polls there, and voters who show up to election sites without acceptable identification will be forced to cast a provisional ballot. According to state law, these voters "may submit a copy of one of the required forms of identification to the electoral board in person or by facsimile, electronic mail, or other means by noon of the third day after the election." This means voting may not be completed in Virginia until noon on Friday. The Richmond Times-Dispatch reports that poll workers will begin counting provisional ballots as soon as identification is presented, but counting could extend up to a week after Election Day. In the 2008 presidential election, less than 5,000 provisional ballots were cast in Virginia, but the state's voter ID law passed after that election, could increase the number this time around. Unlike some voter ID laws, Virginia's statute allows voters to present a wide range of documents to verify their identity, including current utility bills, paycheck stubs or employer-issued photo ID cards. In Wisconsin, where a brutal gubernatorial recall vote was fought in and out of the courts over the last two years, Obama campaign staffers are looking for a fight over voter intimidation inside polling places where they contend election officials have been overzealous in challenging voters. The campaign says it has 1,000 volunteer lawyers statewide to address the challenges. In Iowa, the fighting has already started. The New York Times reports that: Republicans on Sunday night accused Democratic operatives of encouraging older voters to illegally fill out absentee ballots for their family members. A letter to the state's top election official from the chief counsel of the Republican National Committee said that a news report of "the alleged conduct of Democratic and Obama operatives, if true, is highly disconcerting." PHOTOS: America Votes: Election 2012 Florida is unlikely to be the decider this time, but given its history, early voting snafus have some observers worried. An election official in Miami-Dade county spontaneously extended early voting hours over the weekend, then canceled them, then opened them up again. The Tampa Bay Times has a thorough list of potential problems here. Again, mounting numbers of provisional ballots pose a problem if the race is close and goes to a recount. In a turnaround, the Republican National Committee has also raised questions in the last week about electronic voting machines switching votes from Mitt Romney to Barack Obama in Nevada, Colorado and elsewhere. Traditionally, it has been the left that has given credence to the idea that electronic voting machines are secretly programmed to steal elections. As for troubles from Hurricane Sandy, it appears that the remnants of the storm, while still very unpleasant for many, will not complicate the selection of our next president, though its after-effects continue to make life difficult for New Jerseyites and New Yorkers as they try to vote. 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