TALLAHASSEE -- Balloting mishaps, confusion and alleged voter fraud won’t mean much in the post-election analysis if Tuesday’s presidential election isn’t close and Florida doesn’t matter.

But with polls indicating a tight race between Barack Obama and Mitt Romney, the slightest glitch — be it a jammed optical scanner in North Miami or a spike in provisional ballots in Gainesville — could be memorialized as this campaign’s hanging chad.

“In close races, an entire state’s elections process goes under the microscope,” said Ed Foley, an Ohio State University law professor and elections expert. “With that type of scrutiny, things always turn up.”

Here are five issues that could grab the national spotlight by the time official results are certified.

Long ballots

There are 11 constitutional amendments on this year’s ballot, making it the longest in Florida history.

“Either it happened that way by accident, or it was an ingenious strategy to clog up the polling places,” said Monica Russo, president of the SEIU Florida State Council, the governing arm of the labor union. “In the early voting so far, they are the cause for the long lines.”

In Miami-Dade, early voting wait times in some precincts stretched from four to eight hours.

“It’s taking voters a very long time to read it,” said Judith Brown Dianis, co-director of the Advancement Project, a Washington, D.C., a civil rights nonprofit founded in 1999. “Some voters are taking as long as an hour to fill it out.”

Longer ballots mean more paper that needs to be fed through scanning machines, increasing the odds for jams — and longer delays.

Provisional ballots

Four years ago, 30,000 Florida residents voted regularly despite not informing elections officials that they had moved until they arrived at the polls. As long as a clerk could confirm their registered status — and that they had not already voted in their former precinct — they could vote like everyone else.

But a 2011 elections law forces any Florida voter who moves outside their county without updating their registration by Election Day to vote by provisional ballot. These voters then have to verify residency by 5 p.m. Thursday — or lose their vote.

College students are particularly at risk.

“We could have a scenario where we have tens of thousands of provisional ballots because of this new requirement,” said Deirdre Macnab, president of the League of Women Voters. “Think about the number of students at our community colleges and universities who will encounter this, and the delays this will cause at the polls.”

About half of all provisional ballots were rejected in 2008, mainly because voters didn’t bother coming back to verify their status, said Daniel A. Smith, a University of Florida political science professor. “It’s a form of double jeopardy,” he said.

Absentee ballots

In Florida and across the nation, more people than ever are voting by mail ballot. Yet these ballots average a rejection rate double that of voting in person.

“Absentee ballots are the next ticking time bomb,” said Nate Persily, a political science professor at Columbia University. “It’s unreliable because it has more opportunities for error. A ballot has to be requested, received, filled out properly, mailed back in time, then it must be counted in time. At each stage, there’s the potential for something to go wrong.”