The Palm Beach County elections tabulation center stopped counting ballots overnight and didn't resume the recount until mid-morning Thursday — just hours before the 3 p.m. state deadline for submitting updated vote totals — despite being far behind schedule to finish recounts in the races for U.S. Senate, governor and commissioner of agriculture and consumer services.

The county shut off its ballot-counting machines Wednesday evening around 8 p.m. and turned one machine back on around 10 a.m. the next morning. Supervisor of Elections Susan Bucher explained that county staffers were trying to find several boxes of ballots that had already been recounted but whose tallies were lost when the ballot-counting machines overheated on Tuesday night and gave incorrect vote totals.

After the county brought in technicians to fix the equipment, elections staff recounted roughly 175,000 early votes and checked the total number of votes to make sure they matched the numbers from before the machines malfunctioned. They didn't.

"It's not okay, and so they're trying to make it back to where we were two nights ago," Bucher told reporters Thursday morning.

The only staff member Bucher trusted to reconcile the discrepancy, information technology manager Jeff Darter, had been awake for nearly 48 hours by Wednesday evening. Bucher sent him home overnight to rest before resuming the painstaking task on Thursday morning.

The machine logs show that when the machines went down they dropped some of the vote tallies from several boxes of ballots, Bucher said. Elections staff were searching for boxes with the exact number of ballots missing from the total vote count to determine which boxes had vote tallies that had been lost when the machines malfunctioned.

"They have the boxes that we believe it dropped and they're going to try and put those boxes back together and add them into the tally and if we can get that by 3 p.m. those are the results we're going to add in," she said.

Bucher wouldn't say exactly how many votes the counts were off by, but said that there were missing tallies from more than a dozen precincts that had "lost substantial numbers of ballots."

The giant windowless warehouse where county workers had been frantically recounting ballots around the clock for five days was quiet and nearly empty early Thursday morning except for a small group of volunteers, lawyers and reporters. Bucher and Darter were back in the tabulation center by 9 a.m. and had restarted the search for the missing tallies by 10 a.m.

But Bucher said she wasn't sure whether elections staff would be able to find the missing ballots in time to finish the Senate recount by the 3 p.m. deadline. Reconciling the vote totals is all they have left to do for the Senate recount.

"The likelihood is slim," Bucher said. "We're going to give it our best shot, but the reality is we were very close two nights ago and then our machines went down. It was not for lack of human effort."

Unlike ballot-counting machines in Miami-Dade, where elections staff finished recounting ballots Tuesday evening, Palm Beach's decade-old ballot-counting machines can only recount one race at a time.

Palm Beach elections staff started with the Senate race between Gov. Rick Scott and U.S. Sen. Bill Nelson and had planned to move on to the governor's race next. However, Bucher had already warned that her staff would not be able to meet the deadline to recount votes cast in the governor and agriculture commissioner races and in a Florida House race. She said earlier in the week that she was confident they would finish counting votes in the Senate race, but after the machine malfunction she was less certain, saying that the county was "in prayer mode to finish on time."

The ballot count discrepancy wasn't the only uncertainty at the Palm Beach elections office. A federal judge ruled early Thursday that Florida's 67 elections supervisors had to give voters whose ballots were rejected over mismatched signatures another two days to fix the problem.

Bucher said her office was still trying to determine their next steps.

"I think there's a lot of things flying this morning and we're trying to figure out," she said. Bucher's office had printed the necessary paperwork for voters with mismatched signatures and was ready to match them, but because Scott had vowed to file an appeal Bucher said she wasn't sure whether the extension would hold.

Palm Beach has at least 931 ballots with mismatched signatures, according to a document from the Secretary of State's office. That's out of a total of at least 3,700 statewide, according to the document, which only included information on 45 counties.