WASHINGTON – Voters flocked to the polls Tuesday in what could be the highest turnout in decades for a midterm election to decide the control of Congress and governors of 36 states.

President Donald Trump isn’t on the ballot. But he barnstormed 20 states since September, arguing that “everything we have achieved is at stake,” as he said at a rally Monday in Fort Wayne, Indiana.

With 435 members of Congress on the ballot, Democrats were hoping the election results would allow them to wrest control of the House and Senate from Republicans. Former President Barack Obama stumped in Miami saying the “character of our country is on the ballot.”

“There appears to be enthusiasm on both sides of the aisle,” said Lara Brown, director of George Washington University’s graduate school of political management. “The idea that two-thirds of Americans would in fact turn out to cast a vote one way or another for or against the president is relatively extraordinary.”

About 40 million early votes were likely cast, said Michael McDonald, a professor at the University of Florida who tracks the figures. In the last such congressional elections in 2014, there were 27.5 million early votes.

Ohio Secretary of State Jon Husted said more than 884,000 Ohioans had cast absentee ballots by mail this election and almost 430,000 had cast an absentee ballot early in person. The statewide mail-in total is 23 percent higher than the 2014 midterms and the in-person total is nearly three times the 146,000 ballots cast in 2014.

Brevard County, Florida, set a modern-day record for a midterm election with 63.06 percent turnout by 5:10 p.m. The previous record was 62.7 percent in 2002.

"Early turnout appears to be pretty strong," said Bradford Queen, a spokesman for the Kentucky Secretary of State's office.

Higher turnout exacerbated problems such as long lines and voting-machine malfunctions at states including Georgia, Arizona, Florida, New York, Michigan and Texas.

“Turnout is exceptionally high so they might not have been prepared,” said Laura Stoker, a political science professor at University of California, Berkeley, who studies voting and elections.

By 5 p.m. EST, a national hotline for problems at the polls already had fielded more than 24,000 calls and 1,759 text messages about problems such as sites not opening on time, machines not working and long lines.

“It is a reflection of the great interest in this election cycle and also sadly a reflection of the problems and barriers that most voters have faced this election season,’’ said Kristen Clarke, president of the National Lawyers' Committee for Civil Rights Under Law, which led the coalition of more than 100 civil- and voting-rights groups.

For this election, 41 states use equipment that is at least a decade old, according to a report by the Brennan Center for Justice at New York University. In 33 of those states, election officials say they must replace their machines by 2020, but in most cases don’t have the money to do so. The risk is that older machines break down and are more susceptible to malicious software.

Congress approved $380 million this year for states to improve their election security. But longer term, states will need to update their voting technology and auditing, according to John Fortier, director of the Democracy Project at the Bipartisan Policy Center.

“There are still some major long-term challenges that we will need to address in the next several years to improve that security more,” Fortier said.

An array of federal agencies monitored the election as it unfolded, including the departments of Justice and Homeland Security, intelligence officials and the FBI. By 9 p.m. EST, Homeland Security officials said there was nothing significant to report and that there were no widespread cyberattacks.

Here were some key spots for reported voting problems:

Georgia

Common Cause, a member of the Election Protection coalition said it had received reports of "voting machines going down in large numbers across the state."

A group of Georgia voters filed a lawsuit in U.S. District Court in Atlanta to stop Secretary of State Brian Kemp from presiding over the election because of concerns about his fairness. Kemp, a Republican, was running against Democrat Stacey Abrams for governor.

In Gwinnett County, Georgia, voters at several polling places reported problems with voting machines running out of battery power and not having power cords, according to 11Alive.com television news.

"The line started to build," said Nick Alexander, 50, who arrived at Anderson-Livsey Elementary School in Snellville just after the polls opened at 7 a.m. "The polling director informed us that the batteries had died in the polling machines and someone was going to get power cords."

The Gwinnett County communications director confirmed that the machines were running on battery power and the batteries ran out. He did not know how many machines may have been impacted by the problem.

The NAACP Legal Defense Fund said the move of a polling place in Grady County, Georgia, hurt the ability of a significant number of black voters in that precinct to vote.

At Pittman Park Recreation Center in southwest Atlanta, voters reported waiting up to three hours to cast their ballot. Poll workers told USA TODAY they were initially operating with three voting machines until elections officials brought five more machines just before noon.

“This is purposeful,” said Gaylon Calhoun, 71, who waited two hours to vote. “They are diluting the black vote and it’s as simple as that.”

Around lunchtime, volunteers were handing out pizza and bottled water to voters in line.

“This is classic voter suppression,” said the Rev. Jesse Jackson, the civil-rights leader. “There’s a historical struggle here to protect our right to vote.”

Polling hours were later extended in Pittman Park and in precincts near Spelman and Morehouse College.

Indiana

Heavy voter turnout caused a computer-related meltdown in Johnson County, Indiana. But county officials decided the problem wasn’t bad enough to keep the polls open later.

Voting stalled in some places about 11 a.m. because the voting machines had trouble communicating with electronic poll books, according to Phil Barrow, chairman of the Johnson County Election Board. But voters could return by 6 p.m., he said.

"Voting is just so heavy it’s overloaded our service provider," Barrow said. "They are having problems throughout the state."

Amy Bohannon, 32, was in line for 50 minutes at the Nest Event Center in Greenwood and things came to a standstill around lunch time.

“One of the volunteers came out to tell us that all servers in Johnson County are essentially down,” she said. “It’s taking three to four minutes to process someone to even vote.”

Michigan

Voters around Detroit found malfunctioning machines and long lines at various polling places this morning.

Rex Nagy, a retired voter in Redford Township, said that his polling place at Pierce Middle School was relying on just one broken voting machine that he was told had not been tested before Election Day. Everything was at a standstill while around 100 people waited for the machine to get fixed.

"It stinks, it really does," Nagy said. "So many people were upset."

At Greenfield Elementary in Oakland County's Southfield Township, resident Sarah Donovan was told her voting machine was out when she arrived to vote at about 8:30 a.m. Many of the 20 to 30 others waited, but she went home to call the township.

The machine's batteries ran out after two hours, said the Southfield city clerk Sharon Tischler. It was plugged into a surge protector, but the protector was set to the "off" switch, which was fixed by a custodian.

Other machines in Wayne County "froze" this morning and have since been restored, said spokesperson for the clerk's office Lisa Williams-Jackson. Voters at both Riverside Elementary in Dearborn Heights and Addams Elementary School in Redford experienced the issue.

Ballots cast during troubleshooting were placed in the auxiliary bin to be counted after polls closed.

Mississippi

Secretary of State Delbert Hosemann was frustrated that police in Jackson, Mississippi, placed roadblocks near some polling places under a previously scheduled exercise.

Jackson Police Chief James Davis said the “administrative roadblocks” had been set up as part of a weeklong initiative called “Operation Safe Streets.

But Hosemann criticized the use of checkpoints on Election Day.“We don’t even allow uniformed officers in the precincts for that very reason,” Hosemann said. “I mean, why are they stopping people?”

Pennsylvania

William Curtis, a member of the National African American Clergy Network in Pittsburgh, said his group has gotten several calls from voters who went to their usual polling site and were told they weren’t in the right place. He said some voters found their polling sites closed.

“Pennsylvania is playing major games,” said Curtis, who also complained about long lines at some sites. “We’re having to do overtime to" identify correct polling sites for voters.

A man allegedly threatened to “shoot up” a polling place near Pittsburgh, in Washington County, Pennsylvania, according to KDKA-TV.

According to the criminal complaint, Christopher Thomas Queen, 48, of Claysville, arrived at the South Franklin Volunteer Fire Department social hall to vote, but was told he wasn’t registered. Queen then allegedly became angry, said he was going to get a gun and “shoot up” the polling place, and then quickly left.

Queen, who was apprehended, faces charges of terroristic threats and disorderly conduct.

Texas

Texans submitting ballots in early voting reported problems with voting machines switching some of their selections, a problem state officials said was connected to Hart eSlate machines used in about 30 percent of counties in the state. They said it can occur when users fill out and submit ballots too quickly. Voters should double-check their selections shown on a screen before submitting their ballots.

A state judge ordered Harris County to extend voting hours at nine polling places that failed to open on time.

A Harris County election judge was relieved of her job and charged with misdemeanor criminal assault after a racial confrontation with a voter, according to the Houston Chronicle.

The voter, Rolanda Anthony, said she was asked to fill out a residency verification form. Before she could respond, alternate election judge Juanita Barnes moved close to her and began yelling that she had broken the law by not updating her identification. But Anthony said she hadn’t moved.

Barnes, who is white, then told Anthony, who is black, “Maybe if I’d worn my blackface makeup today you could comprehend what I’m saying to you,” according to the Chronicle. Barnes later allegedly bumped Anthony, the paper said.

Barnes was relieved of her duties and left the building about noon after sheriff's deputies and two lawyers and an investigator from the Harris County Attorney's Office arrived to take reports. Barnes declined to answer questions as she was left the building.

Harris County Sheriff Ed Gonzalez said the woman was given a Class C misdemeanor citation.

Customs and Border Patrol cancelled a "crowd control" exercise in El Paso in preparation for caravans of immigrants walking across Mexico toward the border, saying it would be rescheduled for another day. But Common Cause of Texas tweeted that the abundance of uniformed officers might discourage voting.

Arizona

Election Day got off to a rocky start when voters in one town outside Phoenix showed up to vote only to find their polling place had been foreclosed upon the day before.

Maricopa County Recorder Adrian Fontes said the landlord of the building, which appears to be a strip mall, locked it overnight after workers already had set up the polling place. There are ballots inside the building, he said.

Civil rights groups urged Maricopa County to keep polling places open later than the 7 p.m. scheduled closing.

"We will use every tool in our arsenal to ensure that those voters who sought to participate and found shuttered polling sites or broken machines are able to participate before the closing of the polls," Clarke said.

Florida

Residents in parts of the Florida Panhandle devastated by Hurricane Michael just a few weeks ago had to head to an assortment of “voting supercenters” in churches, county election offices, and, in Panama City, a shopping center.

"I am pleased to report that all polls opened statewide on time, and voters are casting ballots in all precincts," Secretary of State Ken Detzner said in a polling update.

More than 5 million Floridians already cast ballots by mail or in early voting, according to Detzner's office. That far outstrips the 3.2 million who cast early or mail-in ballots in 2014 – a potential sign that turnout could be heavy today.

Take the USA TODAY Elections Quiz here.

Contributing: Nicquel Terry Ellis, Cincinnati Enquirer reporter Dan Horn, Arizona Republic reporter Jessica Boehm, Associated Press, El Paso Times reporter María Cortés González

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