Election officials gear up for single biggest day of voting during coronavirus, as Trump rails against vote by mail

President Donald Trump's recent tirade against mail voting was a defiant attempt at elevating his argument of voter fraud -- without evidence -- but it comes as the largest single day of voting since the onset of the coronavirus crisis is set to take place next week.

Even as Trump seeks to turn the issue into a pitched battle, election officials in a number of states, including those run by Republicans, are expanding access to the voting alternative as part of their broader preparations amid the pandemic for the June 2 election.

The president, who has often railed against mail voting by alleging it is ripe for fraud, stepped up his assault last week by targeting efforts in two battleground states -- Michigan and Nevada -- aimed at making it easier to obtain an absentee or mail-in ballot. He threatened to cut off federal funding to those states over what he claimed were "illegal" tactics.

Election officials in both states refuted Trump's attacks, with a spokesperson for Michigan's Democratic secretary of state calling Trump's tweet "false," and Nevada's Republican secretary of state saying the shift to a mail-in election was done "legally."

But the president continued his attack over Memorial Day weekend, tweeting, "The United States cannot have all Mail In Ballots. It will be the greatest Rigged Election in history" and insinuated that advocates of mail-in voting are using the pandemic "for this Scam."

Election experts told ABC News that there has been no widespread fraud in mail voting and that the practice does not decisively give one party's camp an edge over the other.

Efforts to encourage vote-by-mail are coming from Republicans, too

Trump's latest broadside on vote-by-mail comes against the backdrop of seven states, plus the District of Columbia, abruptly changing their blueprint for running elections to adjust to social distancing and other state and federal guidelines ahead of presidential primaries on June 2.

But in those states, despite the president's rhetoric on mail voting, a host of Republican state parties, in Pennsylvania, Indiana and New Mexico are encouraging voters to cast ballots by mail or absentee.

"For several weeks now -- really well, the last month -- we've been in regular cadence of letting all of our folks know about the ability to vote by absentee in a no-fault manner," Indiana Republican Party Chair Kyle Hupfer said. "We haven't been too worried about that."

In Pennsylvania, voters can even request an absentee ballot right on the state GOP's site, with detailed instructions on how to maneuver the voting alternative.

Even some GOP candidates across the seven states are urging voters to use the prominent voting alternative.

In the same video that Mark Ronchetti, a Republican running for Senate in New Mexico, underscores the stakes of his election as a "chance to elect a conservative who will stand with President Trump," he also encourages voters to cast their ballots by mail or in-person, providing supporters with a link to request an absentee ballot on his website.

Matt Rosendale, a GOP candidate for Montana's at-large House seat, also shared a video outlining how to receive a mail ballot to "send a proven Trump conservative to Washington."

And GOP congressman, Brian Fitzpatrick of Pennsylvania's 1st Congressional District, pushed for voters to request a mail ballot before his state's deadline.

Election prepping during a pandemic

Despite Trump's attempts to cast doubt on the integrity of the primary tool for voting during the crisis, election officials are now gearing up for one dayof contests -- second only to Super Tuesday -- that look far different from only a few months ago.

In interviews with election officials across the country, most are moving quickly to prepare their staff and voters for the changes that the coronavirus placed on voting administration. Some states, like Rhode Island and Montana, have instituted changes to their voting system in recent years which have widely expanded vote-by-mail procedures. Others, like Pennsylvania and Indiana, are working around the clock to prepare voters and elections officials for the massive influx of absentee ballot requests.

Before the pandemic, of the seven states and the nation's capital voting on June 2, six allowed for no-excuse absentee voting. In late March, Indiana's elections board ordered the expansion of access to absentee mail-in voting to all voters in the Hoosier state -- without requiring an excuse.

Across geographies and party lines, secretaries of states, local election boards and candidates themselves have given a strong endorsement of the absentee voting process, encouraging voters to request their ballots through applications in states which require them.

In New Mexico, one of the states which hit early benchmarks for re-opening, officials have partnered with the state workforce department to match those who filed for unemployment with local election boards who are short-staffed ahead of the primary.

As the country bolsters its vote-by-mail programs, advocates raised concerns about Native American voters, many of whom live in rural areas of New Mexico and may not have access to resources needed to vote-by-mail.

Some rural post offices -- which are often the closest to Native American reservations -- are only open during limited hours. The shortened operating hours put more constraints on when and how communities are able to send and receive mail, but state officials say ample in-person voting will be available.

"We're basically having a regular election, like we normally would. It's just that we are encouraging everyone to use an absentee ballot and vote from home," Alex Curtas, a spokesperson for the New Mexico secretary of state, told ABC News.

Curtas said the vilification of absentee voting is disappointing: New Mexico, like most states, has safeguards in place to prevent tampering with an election.

"There are these safeguards and bulwarks against people trying to tamper with an election," he said. "Some people try to make a bigger deal out of it than it is."

Pennsylvania, Indiana readying for potential long lines and backlogs

Last year, lawmakers in Pennsylvania, which reported nearly 900 new coronavirus cases on Friday, implemented a vast expansion of absentee and vote-by-mail procedures, already inciting apprehension -- especially when coupled with the state's status as a 2020 battleground.

Suzanne Almeida, the interim executive director for Common Cause Pennsylvania, a voting rights organization, told ABC that for officials in Pennsylvania, "this was never going to be an easy election."

"Pennsylvania in 2020 was always going to be crazy. It's a swing state in the presidential election year. And then on top of that, in 2019 we passed historic voting reform that gave us vote-by-mail for the first time, and changed the voter registration deadline closer to election day," Almeida said.

Advocates are worried that larger cities like Philadelphia and Pittsburgh, which have seen significant reductions in polling places, may present issues like long lines and wait times.

In Philadelphia, there will be 77% fewer polling places for the June 2 primary, with only 190 in-person polling places this election, a dramatic decrease from the 831 in last November's municipal election, local election officials confirmed to ABC News.

In Indiana, which is already entering phase 3 of re-opening, officials have seen delays due to the volume of absentee ballot requests, according to Russell Hollis, the deputy director of the Marion County clerk's office, home to Indianapolis.

"There are some delays, particularly with the volume of requests that we've had. It's very difficult to tell whether the post office is a factor," Hollis said.

Hollis said the vast increase in ballot requests is what has put the most strain on officials.

In 2016, the county mailed less than 6,000 absentee ballots. With days remaining until the final deadline, county officials had already mailed over 71,000 ballots to voters.

Upper Midwest red states embrace vote-by-mail

Elections officials in Montana, a state which has managed to fend off the spread of the virus with under 500 reported cases, echoed that assurance with their absentee process, saying a hiccup with a ballot is rare and often quickly resolved.

"If (a ballot) gets rejected, we contact the voter and let them know, and they can come in and resolve it," Eric Semerad, the Gallatin County election administrator, said. "It's very, very rare that that happens at all. It's usually forgetfulness, or household errors, things like that."

In South Dakota, which saw the highest number of COVID-19 cases per capita for the region in mid-April but currently has one of the lowest fatality rates in the country, election officials are confident the Tuesday primaries will run smoothly.

"One gift we were given is Wisconsin," South Dakota Secretary of State Steve Barnett, a Republican, told ABC News of the Badger's state April 7 spring election, which took place at the height of the state's lockdown. "They weren't able to model after anybody else -- we were all on the sidelines kind of watching them. But we've had enough time to prepare for this now."

"I think we're going to be in good shape," he added.

The state already had a robust vote-by-mail system, but under Barnett's leadership, election officials sent application forms to every registered voter in the state -- the same move Michigan's secretary of state announced last week that triggered Trump's attack. Barnett said that they were just using "the tool already in our toolbox" to encourage voters to use the absentee option, a state-wide push done for the first time to his knowledge.

"There's no blueprint, obviously, nobody's ever seen anything like this before," he said of conducting an election during a pandemic.

For in-person voting on election day, there have been some election worker shortages leading to the state reducing the number of polling sites. But Barnett doesn't anticipate "a lot of pressure on the polls," since there has been an influx of absentee ballots already returned, which is already nearly half of 2016's total election turnout. Poll workers will have hand sanitizer, Clorox wipers, gloves, masks and one-time use pens at polling sites.

In and around the nation's capital, election officials lean on mail ballots

In Washington, D.C., which has seen one of the starkest racial divides when it comes to the impact of the coronavirus, all of the nearly 150 precincts were closed due to the pandemic.

City officials urged residents to cast their ballots by mail, but for those who were unable to do so, 20 in-person vote centers will be available to every voter, no matter what address they are registered at.

Rachel Coll, the spokesperson for the city's Board of Elections, touted that its vote-by-mail system has been in place for 10 years and said they are strongly encouraging residents to use the no-excuse option for the primary.

The city, though, has trounced 2016's special ballot requests in the primary, which amounted to less than 8,000. In 2020, with days to go until hitting the deadline, the city has received more than 70,000 requests for a mail-in ballot. Washington also extended the deadline to receive a ballot to June 12, although they must be postmarked by June 2, to allow for more time for ballots to be received.

In Maryland, however, election officials are facing challenges with vote-by-mail, after opting to use a third-party vendor to handle printing and mailing ballots, according to a spokesperson for the state board of elections.

The board has expressed disappointment with the speed of the vendor, the spokesperson said, after it was reported by the Baltimore Sun that ballots in Baltimore County were marked as sent when they had yet to be.

The state used a special election in late April as a test run for their primary, which was ordered to be an all-mail election due to the pandemic. Election officials, who ran into issues during the special election when ballots sent to voters had conflicting instructions, are hoping for a smoother run this time around.

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