Even before voters head to the polls on Tuesday, issues with early and in-person absentee voting and disputes over provisional ballots and voting equipment have popped up in several key swing states.

Myrna Peralta, left, and other voters react after the elections office in Miami-Dade County reopened its doors to voters who waited in long lines for an absentee ballot in Doral, Fla., Sunday, Nov. 4, 2012. (Alan Diaz/AP)

The most recent instance came in Florida on Sunday, where voters waited in a long line in Miami-Dade County to cast in-person absentee ballots, after officials allowed extra time for voting. (Early voting technically ended on Saturday, as Gov. Rick Scott (R) had previously ended early voting on the Sunday before Election Day.)

Voting was halted temporarily in the county on Sunday, and initially, the apparent cause was the massive turnout that stretched personnel and equipment to its limit. The Miami Herald reported that the mayor of Miami-Dade never signed off on the additional voting time, a factor which also contributed to the delay.

The snags ahead of Election Day in Florida are not the only voting-related complications officials and voters in key swing states have had to contend with. Here's a look at a few other bumps if the road in the closing days of the campaign. (The Election 2012 blog has a detailed look at issues dating back to early October here):

 * Ohio: Dispute over provisional ballots A new standoff over provisional ballots was sparked Friday when Secretary of State Jon Husted (R) instructed election officials to reject provisional ballots with incomplete identification information. Voters, not poll workers, will be responsible for filling out that information. Critics of the move contend that it increases the likelihood of error, and is at odds with a previous legal decision. The entire legal battle probably won't be resolved before Election Day.

If the outcome in Ohio isn't in doubt Tuesday night regardless of provisional ballots, then the whole matter may be little more than a footnote on the election season. But if the result of the presidential race or other high-profile contest isn't decided in Ohio, look for this matter to receive much more attention.

* Republican National Committee asks for voting machines to be re-calibrated in six states Citing concerns last week that voting machines in several states could populate votes for President Obama when Mitt Romney was selected, the RNC called for machine re-calibration ahead of Election Day. Several of the states have pushed back, saying that there is insufficient evidence of malfunction to merit re-calibration.

North Carolina, a key swing state in the race between Obama and Romney, is not going to re-calibrate, arguing that miscast ballots caused by machine error are virtually nonexistent.

Nevada Democratic Secretary of State Ross Miller responded to the RNC with a letter saying the committee presented insufficient evidence to back its claim.

In Colorado, GOP officials pointed to just one example of a malfunctioning machine.

* New York: Possible extra day of voting In the aftermath of Hurricane Sandy, if turnout is under 25 percent, county election officials could petition the state for an extra day of voting, CNN reported. A state official told CNN that a possible second day of voting would be scheduled within 20 days of Tuesday. New York is not a swing state at the presidential level, so whatever happens there won't likely factor into the race for the White House.

* New Jersey: Fax, e-mail voting options Voters displaced by Sandy will be allowed to vote by fax and e-mail.