By TERRY SPENCER and GARY FINEOUT, Associated Press

FORT LAUDERDALE, Fla. (AP) — Florida's election recount drama is intensifying as lawyers return to court and tallying machines break down ahead of a Thursday deadline to complete reviews of the senate and governor races.

Much of the trouble centers on the Democratic stronghold of Palm Beach County, where tallying machines have overheated. That's caused mismatched results with the recount of 174,000 early voting ballots, forcing workers to go back and redo their work with no time to spare.

A mechanic was flown in to fix the problems, but "we don't have a lot of assurances," Palm Beach County Elections Supervisor Susan Bucher told WPTV Tuesday night. Bucher did not immediately respond to messages from The Associated Press on Wednesday.

Meanwhile, lawyers for Democrats planned to ask a federal judge on Wednesday to set aside the state law mandating that mailed-in votes be thrown out if the signature on the envelope doesn't match the signature on file with election authorities.

The developments are sure to fuel frustrations among Democrats and Republicans as the recount unfolds more than a week after Election Day. Democrats have urged state officials to do whatever it takes to make sure every vote is counted. But Republicans, including President Donald Trump, have argued without evidence that voter fraud threatens to steal races from the GOP.

The state elections department and the Florida Department of Law Enforcement, both run by Republican appointees, have said they have seen no evidence of voter fraud. A Broward County judge challenged anyone who has evidence of fraud to file a report.

As it all plays out, the Republican candidates for governor and Senate, Ron DeSantis and Rick Scott, still hold the narrowest of leads over their Democratic counterparts, Andrew Gillum and Bill Nelson.

While the counting goes on, there are now four lawsuits pending in a Tallahassee federal court that seek to throw out ballot counting rules or extend the Thursday 5 p.m. deadline for recounts.

Marc Elias, a campaign attorney for Nelson, argued ahead of the looming court battle that "we should all be able to agree that the goal here is a legal and accurate count." Republicans have responded by contending that Democrats want to bend or skirt existing election laws to alter the outcome.

"We got to keep the heat on these people to make sure they follow the law," said Republican U.S. Rep. Francis Rooney to reporters on a recount update organized by Scott's campaign.

At the Broward County elections center, about 30 workers gathered around a dozen counting machines counting ballots on Wednesday morning. The process resembled feeding documents into a photocopier - they placed stacks into feeders, which run through about two or three ballots per second. Then workers grab another stack and repeat the process.

Trump on Tuesday called on Democratic Nelson to admit that he lost his re-election bid.

"When will Bill Nelson concede in Florida?" the president tweeted. "The characters running Broward and Palm Beach voting will not be able to 'find' enough votes, too much spotlight on them now!"

Presidents have historically sought to rise above the heated partisan drama surrounding election irregularities. Former President Barack Obama wasn't so publicly involved when a recount and legal process in the 2008 election delayed a Democrat taking a Minnesota Senate seat until July 2009. Former President Bill Clinton struck a lower tone during the 2000 presidential recount, which also centered on Florida.

But this Florida recount has been personal for Trump. He aggressively campaigned in the state, putting his finger on the scales of the Republican gubernatorial primary this summer by endorsing DeSantis. After Election Day, Trump's aides pointed to the GOP's seeming success in the state as a validation that the president's path to re-election remained clear — a narrative that has grown hazier as the outcomes have become less certain.

White House spokeswoman Mercedes Schlapp said Tuesday the president "obviously has his opinion" on the recount.

"It's been incredibly frustrating to watch," she said.

U.S. Senate Minority Leader Chuck Schumer said Trump is attempting to bully Florida election officials out of doing their jobs. Schumer and Nelson, both Democrats, spoke with reporters Tuesday in Washington.

"It's just plain wrong. It's un-American." Schumer said. "If he really wants an honest and fair election, President Trump will stop bullying, harassing and lying about the vote in Florida, and let the election proceed without the heavy hand of the president tipping the scale of justice."

State law requires a machine recount in races where the margin is less than 0.5 percentage points. In the Senate race, Scott's lead over Nelson was 0.14 percentage points. In the governor's contest, unofficial results showed DeSantis ahead of Gillum by 0.41 percentage points.

Once the machine recount is complete, a hand recount will be ordered in any race where the difference is 0.25 percentage points or less, meaning it could take even longer to complete the review of the Senate race if the difference remains narrow.

If the Senate race does go to a hand recount, the deadline for counties to finish is Sunday. But two of the pending four lawsuits ask that a federal judge delay the deadlines so that all counties can finish processing the crush of ballots.

Elias argued that there's no need to rush, since the winner of the Nelson-Scott race won't be sworn into office until January.

Associated Press writers Tamara Lush in St. Petersburg, Florida; Brendan Farrington in Tallahassee, Florida; Jennifer Kay and Freida Frisaro in Miami; and Alan Fram, Darlene Superville and Zeke Miller in Washington contributed to this report.