Heavy rain made for a wet afternoon in Georgia’s 6th Congressional District, although it was unclear if the deluge will have much of an effect on voting as the hours ticked closer to the end of Tuesday ‘s nationally watched runoff between Republican Karen Handel and Democrat Jon Ossoff.

The National Weather Service said storms would likely continue as metro Atlanta, including much of the 6th District area, was put under a flash flood warning until 7:15 p.m. — just after polls were scheduled to close. Besides the rain, election officials so far have reported scattered issues but no major problems otherwise.

Most notably, DeKalb County officials received permission to extend voting hours at two polling locations — Livsey Elementary and in Embry Hills at Holy Cross Catholic Church — until 7:30 p.m. The half-hour extension came after both locations experienced problems early Tuesday with checking in voters.

Polls opened at 7 a.m. in parts of Cobb, DeKalb and Fulton counties for the contest, which is seen as an early referendum on President Donald Trump's administration. Scores of outside groups from both sides have invested in the outcome, using tens of millions of dollars as well as a small army of volunteers to sway voters.

That spotlight has been intensified by the fact that the runoff is the only electoral game in town. Early voting saw more than 140,300 people cast ballots — a 27 percent turnout rate among the district's 526,000 registered voters that local election officials called unprecedented for a special election.

Both campaigns have also bombarded residents inside and outside the district with television and radio ads, with district residents reporting as many as a dozen calls a day and canvassers seemingly knocking nonstop on their doors.

Tony Promiscuo, a hair salon owner from East Cobb, on Tuesday voted for Handel because of what he said was her experience, conservative views on the federal budget and support for the military. Mostly, however, he said he’s looking forward to the election being over.

“I will be so happy not to have them knock on my door,” he said.

State officials also received a complaint Tuesday about campaign signs being too close to a polling location in Cobb at Chestnut Ridge Christian Church, although no formal investigation has been opened.

Georgette Dobkin, a precinct captain for the Ossoff campaign, said they had moved back from the polling station at the request of a poll worker. The state’s mandated buffer for campaigning is 150 feet from the building where the poll is located.

Dobkin said she got involved in the campaign after her college-aged son volunteered as well.

“I kinda thought to myself, ‘I should stop complaining about things from my sofa,’” she said.

Handel cast her ballot in the morning before the showers began, with dozens of reporters and camera crews scrambling for a view of the candidate. She made a point to say Ossoff couldn't do the same, since he lives outside the district near Atlanta's Emory University.

The Democrat said it’s so his fiance can walk to work at Emory University Hospital. Congressional candidates don’t have to live in the districts they represent, but Ossoff said he plans to move to the 6th if he wins.

"I've lived here for nearly 25 years, and I think that's going to make a big difference to the voters in this district," Handel said. Handel added that Tuesday's race "is essentially a jump ball," with polls and pundits predicting a razor-close outcome.

Roughly 50 Ossoff supporters, meanwhile chanted “Flip the 6th! Flip the 6th!” outside of Handel’s polling place.

One of them was Karen Thorpe, a former teacher from Roswell.

“We have an amazing candidate that I am so proud of,” Thorpe said. “I’ve never been inspired by a candidate like I am by Jon. He’s honest and I really think he’s got the right message.”

AJC reporter Greg Bluestein answers questions and discusses what he'll be watching as the votes are counted in Georgia's 6th District runoff between Jon Ossoff and Karen Handel.

In DeKalb, the early morning problem involved poll books that contain electronic lists of voters for each of the locations, one at Livsey Elementary School and in Embry Hills. Poll workers switched to paper back-ups, with the correct electronic poll books delivered later in the morning at each location.

Both locations still opened on time this morning, but the mix-up slowed things down enough that officials sought extended voting times at both locations.

The Georgia Secretary of State’s Office was also notified of the problem, and sent a state investigator.

Chris Cupit, a voter who said he had been first in line at Livsey Elementary, said he was angry at how the situation was handled. He said poll workers seemed caught off-guard and initially told voters they had either already voted or were at the wrong place before they realized what the mix-up was.

When workers then offered paper forms for voters to sign — the correct procedure — Cupit said some voters walked out because of the delay or said they didn’t trust their votes would count.

Also in DeKalb, state officials said a poll worker at St. Luke’s Presbyterian Church in Dunwoody accidentally kicked the cord to that location’s electronic poll book, causing delays as officials had to plug the unit back in and reboot.