Civil rights groups and election officials fielded thousands of reports of voting irregularities across the country Tuesday, with voters complaining of broken machines, long lines and untrained poll workers improperly challenging Americans' right to vote.

The loudest of those complaints came from Georgia, where issues of race, ballot access and election fairness have fueled an acrimonious governor's contest between Democrat Stacey Abrams and Republican Brian Kemp. Abrams, a former state lawmaker, had been vying to be the nation's first black woman governor, while Kemp, the secretary of state who oversees elections, has faced accusations of trying to suppress the minority vote.

In one downtown Atlanta precinct, voters waited three hours to cast ballots after local election officials initially sent only three voting machines to serve more than 3,000 registered voters. In suburban Gwinnett County, the wait surpassed four hours, as election officials opened the polls only to discover that their voting machines weren't working at all, voters said.

Both locations serve predominantly black voters, feeding worries among some voters that specific groups were being disenfranchised amid signs of record turnout for a midterm.

"Look at the people here," said Gabe Okoye, chairman of the Gwinnett County Democratic Party, as he watched mostly black voters at the polling place. "See the demography of these voters."

"If you're going to play tricks anywhere, you're going to do it here," he added.

The wave of complaints from voters came at the end of a campaign season dominated by concerns about ballot access and voting rights. It remained unclear Tuesday how many of the complaints were legitimate, how many voters were affected and whether the problems would affect the outcome of any races.

Some of the anxiety stemmed from a spate of restrictive voting laws passed by Republicans in recent years affecting dozens of this year's closely contested races for House, Senate and governor.

Republicans have said the tough new rules are necessary to combat voter fraud. On Monday, President Donald Trump and Attorney General Jeff Sessions both warned against voter fraud, although studies have found no evidence of widespread fraud.

Voting rights activists argue that the laws disproportionately affect young Americans and minorities, who tend to vote Democratic.

Lots of voters, more problems

The spike in reports of voting problems also coincided with heightened enthusiasm across the country to participate in this year's races, with early voting tallies in dozens of states far outpacing those of 2014.

On Tuesday, elections officials in states including Texas, Alabama, North Carolina, Indiana and Georgia extended voting hours to contend with long lines outside polling locations. Some states, including North Dakota, were also contending with low supplies of ballots and voters still standing in line by Tuesday evening.

A coalition of civil rights groups reported receiving more than 17,000 complaints of voting irregularities by midafternoon — a higher call volume than in any recent midterm election — and referred many of them to state and local election officials, the groups said in a news conference in Washington.

Together, the organizations have deployed about 6,500 lawyers and monitors across 30 states to protect ballot access — more than in any previous election.

"Our goal is to make sure that every eligible American that seeks to have their voice heard is able to do so this election cycle," said Kristen Clarke, executive director of the Lawyers Committee for Civil Rights Under Law, one of the groups that teamed together to monitor elections and run a voter hotline this year. Other members of the coalition include the NAACP, Common Cause and Asian-Americans Advancing Justice.

Reports of broken machines surfaced in numerous states, including New York, California and Arizona. Complaints also emerged of voting machines flipping voters' choices in Pennsylvania, North Carolina, Texas and Illinois.

In New York, Corey Johnson, the speaker of the New York City Council, said the voting precincts were hampered by broken scanners in all five boroughs. Voters stood in lines with ballots in the rain — soaking the ballots and further complicating the process of using electronic scanners.

Voting rights advocates said some of the problems are the result of equipment that hasn't been replaced in more than a decade. The machines date back to shortly after the presidential recount in Florida in 2000, when Congress sent billions of dollars to the states to replace outdated equipment. Another round of replacement is overdue, advocates said.

Across the country, reports about huge turnout were punctuated with complaints about voters who faced obstacles to casting their ballots.

Tribal IDs questioned

In North Dakota, a voting rights lawyer said dozens of Indian voters were being turned away because of problems with their identification. Poll workers were rejecting identification issued by tribal officials, advising voters not to initial ballots even though the law requires it and discouraging voters from casting provisional ballots when they arrived without proper identification, according to Carla Fredericks, director of the Indian Law Clinic at the University of Colorado.

"After I caught a voter who was being denied his right to vote and told him to go back in and request a set-aside ballot, the election worker told me I was interfering and need to leave," said Fredericks, a member of the Mandan Hidatsa Arikara Nation, in central North Dakota.

In Porter County, Ind., where Democratic Sen. Joe Donnelly lost to Republican Mike Braun, a judge ordered 12 polling places to stay open late after the local Democratic Party complained about tardy openings of up to three hours.

"It's a matter a fairness to the voter, without respect to partisan politics," said Monica Conrad, an attorney for the Porter County Democratic Party. Local Republicans unsuccessfully challenged the order by Superior Court Judge Robert Bradford, arguing that the Democrats had not provided enough evidence that polls opened late, said attorney Chris Buckley.

The epicenter of voting anxiety was in Georgia, where the bitter gubernatorial contest has played out as an emotional battle over voting rights.

Tensions mounted in the weeks before Election Day after the revelation that thousands of voter registration applications had been suspended, most of them for people of color or immigrants, under a new state law requiring an exact match between the application and driver or Social Security records. Brittany Herbert, 32, a lawyer, said she arrived at the Pittman Park Recreation Center in Southwest Atlanta at 8 a.m. and found the polling place in chaos. When she tried to check in, she was told she'd have to wait, so she left to go to work and returned around 4:15 p.m. At 5:15 she estimated she had another 45 minutes to wait. "Voting is always really important to me," she said. "I also knew that my family and friends would shame me if I didn't."

A spokeswoman for the Fulton County elections office acknowledged a handful of polling problems Tuesday.

"Today's election is a big one for this state and there are a lot of enthusiastic voters out there," said spokeswoman April Majors. "We're happy about that, but unfortunately the enthusiasm is what is causing the long lines."