This call center in Washington is one of 23 scattered around the country where volunteers — mostly lawyers, law clerks and law students — help people get information needed to vote and take tips about voting problems. (Marvin Joseph/The Washington Post)

It’s 10 a.m. but the room is already warm with body heat and the smell of coffee. Behind the locked glass doors of a downtown Washington office, in a conference room outfitted with 20 phone lines, computer workstations and posters that try to make inspirational art out of single words such as “Dedication,” volunteers are fielding phone call after phone call.

This is one of the front lines in one of the most contentious presidential elections in memory. It is one outpost of the Election Protection Coalition voter hotline, a volunteer-staffed nonpartisan network of organizations devoted to protecting the right to vote. The advocates behind the operation say they are worried that more than any presidential election in the past 50 years, the 2016 contest carries a pronounced risk for impropriety and mischief. They, too, like Donald Trump, worry that the election could be rigged.

But not in the way the Republican nominee has insisted it will be — by “inner city” residents resorting to fraud to help elect Hillary Clinton. They are more concerned about a combination of ordinary and extraordinary voter confusion; a lack of pre-election federal oversight and the specter of in-person voter intimidation by Trump supporters.

“What we face is a combination that is both dangerous and almost unprecedented,” said Thomas A. Saenz, president and general counsel of the Mexican American Legal Defense Fund (MALDEF), a coalition member organization.

In response, the coalition has set up 23 call centers across the country for what it thinks will be a fractious and contentious Election Day resembling the ugly campaign that preceded it.

The call centers across the country are operated by the roughly 100 organizations that make up the Election Protection Coalition and aim to prevent voter suppression. (Marvin Joseph/The Washington Post)

“We’ve spent hundreds of millions of dollars with the sole mission of getting more people to vote,” said Lindsay Walker, a spokeswoman with the Republican National Committee. “We’ve revived our voter registration program and put a priority on early and absentee voting, and have hired more people and trained more organizers to ensure we can do it than in any point in our party’s history. “

GOP officials in Michigan plan to dispatch more than 100 lawyers to polling sites around the state to identify and block what they see as the real possibility of “massive” voter fraud. In Pennsylvania, Republicans filed suit to challenge a state law that bars individuals from monitoring polling site activity in a county where the individual does not live.

“It’s all extremely problematic,” said Rashad Robinson, executive director of the tech-savvy civil rights group ColorOfChange, also part of the election protection circle. “Fortunately, Trump’s psychology is such that he’s pretty much drawn us a map of where we need to be and what we need to do to be prepared.”

In the days since the coalition’s 866-OUR-VOTE hotline opened, volunteers have picked up more than 50,000 calls. In 90 minutes at the D.C. call center, volunteers helped an Alabama man, originally from Pakistan, who wanted to verify that he was registered to vote and what he should take with him to the polling site.

A woman in Florida was alarmed by an official-looking postcard indicating that the mail-in-ballot she sent several days earlier had not arrived. And a first-time voter in New York called distraught because election officials turned her away from an early voting site saying there was no record of the registration form, which she was certain she had completed and mailed on time.

In addition to providing practical help-desk-level assistance to stressed and distressed voters, coalition officials said they are focused on constitutional obstacles.

They point to the 2103 Supreme Court decision that overturned a provision of the 1965 Voting Rights Act that forced many states and local municipalities, particularly in the South, to get clearance from the Justice Department before changing election laws to guard against discriminatory outcomes. The decision in Shelby County (Ala.) v. Holder ended a process known as pre-clearance. Anita Earls, a civil rights attorney who worked in the Clinton Justice Department and serves as the executive director of the Southern Coalition for Social Justice, said the end of pre-clearance created more work for voting rights advocates across the country.

Catherine Gordon is one of several volunteers at this call center helping people around the country who are having voting issues. (Marvin Joseph/The Washington Post)

That has meant litigating voting requirement changes, registration matters and making contact with election officials after reports that individuals were videotaping or menacing voters outside polling places.

And there are at least 868 fewer polling sites around the country than there were in the 2012 and 2014 elections, according to a report released Friday by the Leadership Conference Education Fund., which said that since Shelby, many poll closings have gone unnoticed and unchallenged.

Back at the Washington call center, volunteer Brittany Brewer, a lawyer who usually handles capital markets and mergers and acquisitions work for her law firm, walked the man in Alabama through the voting process until he felt comfortable.

Brewer logged on to a database in Florida that allows her to check the status of early votes in real time. Brewer asked the woman for a few bits of information, typed them into the system and got an answer: She tells the voter that the state has received and tallied her ballot.

“I’d say that most of our calls fall into three baskets,” said Kim Stietz, a law clerk and one of the D.C. hotline coordinators. “There’s the voter who is confused about some aspect of the registration or voting process or anxious because of the division around the country and the nature of the campaign to date. And there are voters who are dealing with poorly organized state voting systems.”

Examples of the latter occupied a lot of hotline time last week.

Texas passed a strict voter ID law just after the Supreme Court’s Shelby decision. This year, aware of pending litigation challenging the law, election officials printed, distributed and hung posters with ID requirements in early voting locations, Saenz said.

A court then ordered the state to allow those who are willing to attest that they do not have one of the required forms of ID to sign an affidavit then cast a ballot. Still, last week, voters in Texas were reporting to hotline volunteers that they were still seeing the inaccurate posters, and that poll workers were continuing to tell people to have certain forms of ID ready.

The pattern of calls has been particularly intense from Texas counties such as Bexar, which includes San Antonio and a population that is 59.5 percent Hispanic, and Harris, which includes Houston and a population that is 36.5 percent black, Latino or Asian.

Staff at the Lawyer’s Committee for Civil Rights demanded a fix. The Texas secretary of state has issued guidance to county election officials on voter ID, posters and affidavits several times and did so again.

“We don’t know that anyone is trying intentionally to discourage or block voting in Texas,” said Kristen Clarke, president and executive director of the Lawyer’s Committee. “But it is difficult to imagine that officials charged with administering the election were unaware of the change or were not following the case. So we’re absolutely prepared to hold election officials accountable swiftly.”

Last week, the coalition launched radio and digital ads in 20 Texas markets clarifying the affidavit option. And last month in Virginia, the Lawyer’s Committee filed suit after the state’s online registration system failed. During the 36-hour voter registration extension the organization won in federal court, 28,000 people registered online who otherwise would not have been able to vote.