But the early, heavy turnout on and before Tuesday morning didn’t provide much clarity as to where the races stood. Most political analysts said the large number of early voters, absentee voters and people lining up at their polling places suggests both parties have done a good job motivating their voters — meaning, if anything, close races and a very long night for anyone staying up to see the results. Some 38 million had been counted by mid-day election day, compared to 21 million that were counted in total during the 2014 midterm.
According to an analysis provided to NBC News, these included 3 million votes case by people under 30, and 1.7 million cast by individuals voting in their first-ever election.
For those hoping to see the so-called “blue wave” of victories for Democrats for Congress on Tuesday were looking most ardently at New Jersey, Virginia and Florida, with at least one race in South Carolina — for Rep. Mark Sanford’s seat — also in play.
As for the Senate races, Republicans are hoping to pick up seats in five generally Republican states — North Dakota, Montana, Indiana, Missouri and West Virginia — with well-funded, but vulnerable Democratic incumbents.
In the end, the results may well be determined by who has the right to vote. Since 2010 more than 20 states have adopted stricter Voter ID laws, cut back on the number of days that early voting takes place, and purged voting rolls for a number of reasons.
The Brennan Center is running a live blog on its website Tuesday detailed polling place problems.
At first, the center said, the issues were “scattered.” In Detroit, voters showed up at one polling place, only to find that the voting machines were missing. In Houston, Texas, meanwhile, multiple poll locations were experiencing long lines due to technical difficulties with voting machines.
But by mid-afternoon, problems had gotten worse and more widespread.
In Richland County, South Carolina, voting machines at several polling places needed to be recalibrated after it was discovered they were registering votes for the opposite party whenever someone cast a straight, party-line ballot.
Some of the biggest problems were in Georgia, a state with a hotly contested gubernatorial election, where some voters reported waiting up to three hours to vote.
At a polling place in Snellville, Georgia, more than 100 people took turns sitting in children’s chairs and on the floor as they waited in line for hours. Voting machines at the Gwinnett County precinct did not work, so poll workers offered provisional paper ballots while trying to get a replacement machine.
One voter, Ontaria Woods, said about two dozen people who had come to vote left because of the lines.
“We’ve been trying to tell them to wait, but people have children. People are getting hungry. People are tired,” Woods said. Woods said she and others turned down the paper ballots because they “don’t trust it.”
Joe Sorenson, a spokesman for the county’s supervisor of elections, said some precincts “have had issues with express polls,” devices election workers use to check in voters and create access cards for voting machines.
Reports of broken ballot scanners surfaced at polling places across New York City. Turnout was so heavy at one packed precinct on Manhattan’s Upper West Side that the line to scan ballots stretched around a junior high school gym on Tuesday morning.
Poll workers there told voters that two of the roughly half-dozen scanners were malfunctioning and repairs were underway.
William Keung of New York City, sporting an “I Voted” sticker, said in an interview near Suang Wen School in lower Manhattan that he is a longtime voter casting his first midterm ballot.
“Well, I feel like I need to represent,” Keung said. “I’ve been voting for the past couple of years. It’s my civic duty.”
Senator Kirsten Gillibrand is defending a seat she held since 2009, and Keung said he felt it important to stand by her with the Senate now “up for grabs.”
“From my perspective, I need to send a message to the government, to the federal government, that I don’t want someone who Trump supports,” he said. “I’m supporting Kirsten.”
Keung did not experience the long lines reported elsewhere in the city.
“I mean, c'mon this is like going to Starbucks,” he said. “This is easier than Starbucks.”
Nearby, couple Sergio and Siamara Maldonado reported no trouble, but Siamara noted that was not true of other polling sites.
“I work at a senior center, and it was really crowded,” she said.
The couple noted a greater urgency among people of color to exercise their right to vote.
“I think it is important to have the voices of people of color represented, and right now, Trump’s policies that directly impact people of color are negatively,” Siamara Maldonado said, searching for the words. “It’s just traumatizing, and we need to do better and get more Democrats in office.”
Regina Perez, a 52-year-old working for the Department of Education, declined to discuss how she voted but emphasized the importance of her vote.
“I try to vote in every election,” Perez said. “I think every vote counts.”
Voters in Brooklyn reported long lines and disorganization at polling places. A family said two of three scanners were not working when they arrived but were fixed by the time they got to them.
Alex Payne, 32, said, "It went fast up until the scanner, I think the scanners were backed up, but other than that it was pretty quick, the line wasn't too bad." He said he was inside for 15 to 20 minutes.
There was also confusion in Phoenix, Arizona, after a polling site was foreclosed on overnight. The owners of the property locked the doors, taking election officials by surprise. Voters had been sent to another precinct nearby, but Maricopa County Recorder Adrian Fontes tweeted that the location in Chandler was up and running shortly after 7 a.m. Tuesday.
For about an hour after polls opened Tuesday morning, a Sarasota County, Florida, precinct had to tell voters to come back later because their ballots were not available.
Adam Klasfeld contributed to this report from Manhattan; Amanda Ottaway reported from Brooklyn.
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