Updated at 3:50 p.m.: Revised to include additional information.

AUSTIN -- Texas Democrats are pushing for the May 26 runoff election to be carried out entirely through mail-in ballots, amid fears of the continued spread of the novel coronavirus.

The disease is upending the way candidates campaign, with many furiously canceling fundraisers and block walking in favor of virtual events.

While Republican Gov. Greg Abbott cited COVID-19 in postponing a special election set for early May, it remains to be seen whether the runoff or other local elections will be similarly delayed. Abbott will be making a decision shortly and said “everything’s on the table.”

Past and present election officials caution that shifting the contest to mail-in only, as the Texas Democratic Party is requesting, would be a major undertaking.

“It’s hard enough getting people to vote, especially in a runoff election. How are they going to logistically get mail-in ballots to everyone?” said Carlos Cascos, who was Texas Secretary of State from 2015 to 2017. “Pushing it back 30 or 45 days may be the safe harbor to use.”

In the runoff election, voters are choosing the Democrat who will challenge Republican U.S. Sen. John Cornyn in November and party nominees in a slew of other local races. Also at risk are municipal and school board elections scheduled to take place on May 2.

Democrats in the runoff for U.S. Senate are focusing campaign efforts online.

State Sen. Royce West of Dallas said Tuesday his campaign has converted to a “100 percent virtual and digital operation.” Similarly, the campaign for MJ Hegar of Round Rock reported setting up virtual events, virtual phone banking and texting from home. And Cornyn announced Tuesday he was suspending all campaign-related activities, including fundraising, volunteer efforts and special events.

Democratic Party Chairman Gilberto Hinojosa said it doesn’t seem viable for the state to hold “meaningful elections in May” given the spread of the virus.

“All eligible voters will not be able to participate in those elections with polling place-based voting,” he said in a statement. “An all-mail election, in which county election officials mail a ballot to every registered voter, is the only option that guarantees Texans' right to vote while also protecting public health.”

In Texas, only residents over age 65, those with disabilities and people out of the county or in jail on Election Day are eligible to vote by mail. In the March 3 primary, that amounted to roughly 206,000 votes out of more than 2,000,000 cast in early voting, according to state figures.

Williamson County elections administrator Christopher Davis said the infrastructure isn’t in place to mail every voter a ballot before the May 26 runoff election.

“It would take orders of magnitude: more money, resources, personnel,” said Davis, the immediate past president of the Texas Association of Elections Administrators. Dallas County Elections Administrator Toni Pippins-Poole did not respond to a request for comment.

But in-person voting presents its own set of challenges. Cities across Texas have restricted crowd sizes and public schools that are often used as polling places have been shuttered. Counties that use electronic voting machines with touch screens could have to disinfect them after each voter. Poll workers may be reluctant to show up, as some were on primary day before the virus had begun spreading within Texas.

Over 45% of Bexar County election officials are over age 70, the group most at risk of developing severe cases of COVID-19, said the county’s election administrator, Jacque Callanen.

Texas Republican Party Chairman James Dickey said the party is open to considerations, though he didn’t outline what those may include.

“I am looking at one election at a time given the dynamic nature thus far in how federal, state and local governments have had to respond to Coronavirus,” he said in a statement. “Any changes made to our elections process must be made with great care to defend the rights of voters and the full weight of every valid vote.”

At least five states have postponed upcoming elections, though several others moved forward with voting Tuesday, including Florida, Illinois and Arizona.

Facing the ongoing spread of coronavirus, some states are letting voters mail in or drop off their ballots. Currently, just four states nationwide conduct elections entirely by mail.

Ed Espinoza, executive director of the liberal group Progress Texas, said mail-in voting is the best way forward because the virus could continue to spread for months to come.

“You don’t know how long the pandemic is going to go,” he said.

Civil rights groups sent a letter to the Secretary of State’s office Tuesday saying all voters should qualify for mail-in-ballots given that “merely going to a crowded venue, such as any polling location, in-person constitutes a likelihood of injuring a voter’s health.”

Abbott on Monday postponed a special election to replace outgoing state Sen. Kirk Watson of Austin from May 2 to July 14. The Secretary of State’s office did not respond to questions Tuesday about how the state might make further changes to upcoming elections.

Abbott indicated Tuesday he may not have the authority to change municipal elections and said the decision may be left to local officials. “If I don’t have the legal authority, we may provide suggested guidelines,” he said.

Texas Republicans are planning to move their state convention from May to July, while state Democrats are preparing for an online convention if theirs in San Antonio is canceled.