TALLAHASSEE — The Florida electorate that will vote for the next president has grown by nearly a million voters in the past four years in ways that bode well for the presidential campaign of Republican Donald Trump.

According to numbers released Friday by the Florida Division of Elections, the number of registered voters is 12,863,773, an increase of 7.8 percent, or 929,327 voters, from 2012.

Republicans have 304,320 more voters than they had when Mitt Romney lost Florida by 74,304 votes to Barack Obama.

Democrats gained 95,771 voters in those four years. Their percentage of the electorate slipped from 40.1 percent to 37.9 percent. Republicans held steady, slipping slightly from 35.6 percent to 35.4 percent.

Registered voters belonging to neither party jumped by the highest number — 529,236 — and their share of the electorate grew from 24.4 percent to 26.7 percent.

As of Friday afternoon, 20,737 people who registered late could not be verified, meaning they would have to cast provisional ballots. Based on data from past elections in Florida, provisional ballots get rejected at higher rates than other ballots.

The state said that was because voters provided incomplete or wrong information and county election offices are trying to find those voters 10 days before Election Day.

The judge who extended Florida's voter registration deadline won assurances from state officials Friday that they are doing all they can to verify all new voter forms in time for the start today of mandatory statewide early voting.

U.S. District Judge Mark Walker called a special hearing Friday after learning many of the 128,000 people who took advantage of a weeklong extension would remain unverified because their IDs hadn't been confirmed.

Maria Matthews, director of the Division of Elections, told the judge that voters who remain unverified fall into one of two groups: They submitted incomplete forms or their identities can't be confirmed using a driver's license number or Social Security number.

"Every effort is being made that if we can get everyone registered, we will," she said.

The state said the vast majority of pending applications (19,175) have been sent to county election supervisors, who are attempting to find those would-be voters to resolve any problems.

"At any given time, there will be pending applications," said Pinellas County Supervisor of Elections Deborah Clark. "Not every application that's submitted is complete."

The many possible defects include incorrect birth dates, transposed driver's license numbers, illegible signatures, different names than those on drivers' licenses or boxes left unchecked.

"Those (forms) are sitting in a county. They're waiting for voter action. The onus is really on the voter," Matthews said.

Matthews also identified another 1,300 forms still in the possession of the Division of Elections in Tallahassee waiting to be manually reviewed by state workers.

Matthews said the state reassigned more than 130 workers to help process forms and imposed "mandatory overtime."

As the hearing ended, the judge praised Matthews' agency for "your hard work and your effort" and said: "You certainly provided me useful information."

In an earlier order calling for Friday's hearing, Walker wrote: "It appears that the amount of voters being processed each day has slowed dramatically. … As of now, almost 25,000 voters may or may not have their vote counted in the 2016 general election."

But when he convened the hearing Friday, the judge began by saying: "The questions were not intended to be loaded."

Three weeks ago, Democrats called on Gov. Rick Scott to extend the Oct. 11 voter registration deadline by at least one week after Scott ordered millions of people along Florida's east coast to flee their homes in advance of Hurricane Matthew.

When Scott denied the request, Democrats filed a lawsuit.

Walker initially extended the voter registration deadline for one week, until Oct. 18.

Contact Steve Bousquet at bousquet@tampabay.com. Follow @stevebousquet.