Florida’s U.S. Senate and Agriculture Commissioner races are now in “hand-recount” territory.

State law dictates a hand recount of certain ballots in races where the margin of victory is less than 0.25 percentage points.

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The margin of victory must be equal or less than 0.5 percent of total votes for a

machine recount to be issued in Florida.

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Election Day was Nov. 6, and by midnight that night, Gov. Rick Scott, Republican challenger for the Florida Senate race, declared victory and gave a victory speech. But incumbent Bill Nelson never conceded the race as votes were still being counted and the margin between the two candidates narrowed.

The race for Agriculture Commissioner is a tight one, too.

Two days after Election Day, the race between North Fort Myers real estate appraiser Matt Caldwell and Fort Lauderdale attorney Nikki Fried is still not decided.

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How long does it take for a recount?

Recounting ballots by hand is a tedious process that could drag on for days. State law calls for the election to be certified by Nov. 18. But lawsuits could push that date back, as happened when the 2000 presidential election battle continued until the middle of December when a U.S. Supreme Court ruling ended the recount efforts, handing George W. Bush the presidency.

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George Levesque, an attorney with Gray Robinson's Tallahassee office, says that any hand recount would be much easier now than in 2000, when election officials had to determine whether a "hanging chad" in old punch-card ballots indicated that a voter had meant to vote for a certain candidate.

'Overvotes' vs. 'undervotes'

A manual recount doesn't mean that election officials would look at each of the more than 8 million ballots cast in the state. Instead, they would be examining ballots that tabulation machines said had "overvotes" or "undervotes" in the contested race.

An overvote occurs when the tabulating machine believes a voter cast more than one vote in a certain race. In some cases, voters do fill out more than one bubble for a race. Such "true" overvotes are not counted.

But sometimes a stray pen mark or other voter error can cause the tabulation machines to register an overvote. In such cases, where the voter intent is clear from ballot to election officials, the vote is counted.

"You are trying to figure if it was an intentional overvote, or if you can divine the intention of the voter," Levesque said.

Similarly, an undervote is when a tabulation machine says no vote was registered in a race. Voters sometimes decide not to vote in certain races, perhaps because they feel they don't know enough about the candidates.

But such true undervotes are more common in down-ballot races, not high-profile races like a U.S. Senate Election. And, as with overvotes, sometimes they are caused by voters improperly filling out ballots. If the intent of the voter is clear from an examination of the ballot, the vote is counted.

What if someone concedes?

It appears that Florida will recount the ballots for the 2018 gubernatorial election between Tallahassee Mayor Andrew Gillum and Ron DeSantis. The latest unofficial returns put DeSantis up by fewer than a half percentage point, a lead of 38,515 votes out of more than 8 million votes cast.

Around 2 p.m. the margin had dropped to 0.47 percent.

Gillum conceded the race on election night, but that doesn't have any effect on a potential recount. State law mandates a recount in any race where the margin of victory is less than 0.5 percent unless the candidate with the fewer votes notifies state election officials in writing that they don't wish to proceed with a recount. Gillum has given no indication that he intends to do so.

Contributing: Michael Braun of Naples Daily News and James Call of Tallahassee Democrat

Contact McCarthy at 321-752-5018

or jmccarthy@floridatoday.com.