People demonstrate outside the office of the Broward County Supervisor of Elections in Lauderhill, Fla., on Friday. (Saul Martinez/Getty Images)

The first-ever recount in three statewide races in Florida kicked off in earnest Sunday on a contentious note, with Republican Gov. Rick Scott sharpening his attacks on his opponent in the razor-tight U.S. Senate race and filing a new round of lawsuits against Democratic election officials.

Hours after Scott took to national television to accuse Sen. Bill Nelson (D) of trying to “commit fraud to try to win this election,” his campaign said it had filed lawsuits against Brenda Snipes and Susan Bucher, the election supervisors in Broward and Palm Beach counties, two Democratic strongholds. Democrats called it desperation by a candidate sitting on a precarious vote lead.

Scott made his comments in an interview on “Fox News Sunday” that came after his lead shrank to fewer than 13,000 votes in a race with national stakes. State officials said they have no evidence of criminal conduct in the still-unresolved Senate election.

Pressed on his fraud claim, Scott referred to a lawsuit Nelson has filed to reexamine ballots with signature issues. He also mentioned an incident, being reported by conservative media, in which a lawyer claiming to represent Nelson objected in a public hearing to tossing out a provisional ballot from a noncitizen.

Nelson’s lead recount attorney, Marc Elias, said in a statement that the lawyer at a meeting of election officials in Palm Beach County was “not someone we had authorized to make such an objection. Non-citizens cannot vote in U.S. elections.”

Election administrators are racing against the clock to ­machine-recount ballots ahead of a Thursday deadline to present their findings, with many of the state’s 67 counties beginning the task on Sunday. A more logistically complicated hand recount could follow. The contest will determine the size of the GOP’s Senate majority and settle an expensive fight in the nation’s largest swing state.

That race, as well as the closely watched gubernatorial contest between former congressman Ron DeSantis (R) and Tallahassee Mayor Andrew Gillum (D), have attracted national attention, pitting candidates with sharply contrasting messages and embodying broader disputes between the two major parties during the Trump presidency.

The governor’s comments came a day after Secretary of State Ken Detzner, a Scott appointee, formally ordered recounts in the races for Senate, governor and agriculture commissioner.

In the Senate contest, Scott’s lead over Nelson has narrowed to 12,562 votes out of more than 8 million ballots cast, or a margin of 0.15 percent, according to an unofficial tally Saturday from the state. State law mandates a machine recount if the margin is half a percentage point or smaller.

The governor’s race also has tightened, with DeSantis, a staunch ally of President Trump, ahead of Gillum by 0.41 percent. If it holds, the margin would fall short of the 0.25 percent threshold for a more involved manual recount.

If the margin in the Senate race holds, however, it would be slim enough to trigger a hand recount. In that scenario, officials would have three days to personally inspect ballots with overvotes or undervotes — ballots on which the voter selected no candidate or more than one candidate in the race — provided there are enough to change the outcome. That could spark disputes over whether the voter intended to mark it that way or not.

The election results are slated to be certified on Nov. 20. Newly elected senators are expected to report to Washington this week for orientation. Scott said he has not decided his schedule yet. The Senate will swear in new members in early 2019.

There remains plenty of uncertainty about the path forward. Delays and new legal disputes that could slow the pace of the proceedings are possible.

A lawsuit filed by Nelson seeking another look at absentee and provisional ballots with signatures that don’t match voter registration records will be heard by a federal judge this week and could have a major impact on the election’s outcome.

The machine recount itself will be time-consuming. In Broward County, it could take more than 30 hours just to sort through the pages with races that need to be recounted, according to election operations coordinator Fred Bellis.

GOP criticism of vote counting has centered on Broward and another Democratic-leaning county in South Florida — Palm Beach, where Republicans cited the incident over the ballot involving a noncitizen. The Republicans have upbraided officials there for tallying ballots slowly and not providing enough transparency about their process.

In its new lawsuits against Snipes and Bucher, Scott’s campaign seeks to have authorities “impound and secure all voting machines, tallying devices, and ballots when not in use until such time as any recounts, election contests, or litigation related to the 2018 general election for the office of United States Senator are complete.”

The Scott campaign filed another lawsuit asking that ballots counted in Broward County after a noon Saturday deadline to submit results not be included in the county’s official returns.

In an interview, Snipes denied that she missed the noon deadline. “There’s no rampant fraud here,” she said. Amid some Republican complaints about a recount delay, Snipes vowed, “We’ll make the deadlines if we have to work 24 hours a day.”

Nelson said Scott was operating from a position of desperation.

“If Rick Scott wanted to make sure every legal ballot is counted, he would not be suing to try and stop voters from having their legal ballot counted as intended,” the senator said in a statement. “He’s doing this for the same reason he’s been making false and panicked claims about voter fraud — he’s worried that when all the votes are counted he’ll lose this election.

Broward and Palm Beach counties have come under legal pressure and scrutiny. Last week, judges ordered officials in Palm Beach County to open their canvass to public inspection and Broward officials to release documents the governor had demanded.

Snipes has been the subject of controversies and criticism in the past. In 2016, she was accused of destroying physical ballots while saving digital copies during a lawsuit, a violation of a federal statute.

But Florida’s Department of State said last week that it had seen “no evidence of criminal activity at this time” in Broward County. A spokeswoman for the department, Sarah Revell, said Sunday that statement was still accurate.

Last week, Scott called for the Florida Department of Law Enforcement to investigate the voting in South Florida. The agency has not embarked on a probe, because the Department of State has not presented any allegations of fraud, a spokesman for the Department of Law Enforcement, Jeremy Burns, said Sunday, repeating what he had previously said.

State Attorney General Pam Bondi, a Republican, sent a letter Sunday to FDLE Commissioner Richard Swearingen saying that she was “troubled” that he was not pursuing probes into irregularities, adding, “Your duty to investigate this matter is clear.” She also wrote Detzner to remind him to report signs of criminal activity. Representatives for Swearingen and Detzner did not immediately reply to requests for comment.

Gillum said he has a team of hundreds of volunteers and lawyers fanning out to ensure the recount process is, in his estimation, fair and accurate. He hosted a “count every vote” event at a church in Broward County on Sunday afternoon.

Scott’s campaign said this weekend that it has enlisted 7,500 volunteer recount representatives to monitor the process. Scott also has encouraged sheriffs to watch for any violations.

Reinhard reported from Lauderhill, Fla., and Sonmez from Washington. Amy Gardner in Washington contributed to this report.