Voting security advocates are sounding the alarm about a shrinking window for the United States to prepare for the presidential election during a global pandemic, calling for vote-by-mail options nationwide in case citizens are still advised to avoid public places in November.

But there's been little action among the 16 states that provide absentee ballots only to voters who meet certain criteria – even though some governors back expanded vote-by-mail. Other Republican governors and state election officials flatly oppose sweeping changes.

And there's no consensus in Washington as President Donald Trump called vote-by-mail "a very dangerous thing for this country," "horrible" and "corrupt."

Democrats are pushing to make vote-by-mail available nationally – which would cost billions across all 50 states – in the next coronavirus stimulus bill. Senate Majority Leader Mitch McConnell, R-Ky., said it would be premature to discuss what would go in that legislation while the country still implements the $2.2 trillion package that passed last month.

"We're getting to a do-or-die moment to be able to make the changes that are necessary for a credible election in November," said Lawrence Norden, director of the Election Reform Program for the Brennan Center for Justice at the New York School of Law.

More:As coronavirus pandemic delays 2020 primaries, is it time to worry about the November election?

Advocates don't want a nationwide repeat of last week's Wisconsin primary when voters were forced to weigh safety with exercising their democratic rights. Many stood in line for hours wearing face masks to brave their way to the polls, particularly in the state's largest city, Milwaukee, where only five voting sites were open.

"The little bit of sliver of good news is that we're six, seven months out from the election. So there's still time – just barely – to avoid that," Norden said.

Not as simple as changing the law

Voting experts worry the urgency could get lost as governors grapple with the health emergency presented by the COVID-19 pandemic. Most states imposed stay-at-home orders, and governors turned their agendas almost solely to the crisis as many bid for medical equipment to alleviate shortages in hospitals.

Nearly two dozen state legislatures suspended their sessions or adjourned earlyto follow social distancing recommendations amid the coronavirus outbreak, delaying major policy debates until lawmakers reconvene.

'Unprecedented situation': Coronavirus clamps down on statehouses as legislatures scramble to adapt

Not only are legislative changes or waivers needed in several states, many face uphill climbs – with enormous price tags – to build infrastructure needed for the shift. This includes everything from purchasing enough postage and prepaid stamps for more voters, enlisting people to distribute and sort the ballots, to acquiring ballot-tracker software to track the high volume of voting.

States would need outreach programs to inform people of the changes. Eight states don't even have online voter registration. And as was evident in Wisconsin, states that make absentee ballots available to all voters would need more resources for a high-turnout presidential election.

"Even ordering the paper, which sounds crazy, probably has to start happening at the very latest in May," Norden said. "So we're talking about a matter of weeks before you're going to get to a problem where states are going to have real difficulty meeting the demand for mail-voting changes."

Even if the pandemic wanes somewhat by summer, health experts warn the COVID-19 outbreak could return in waves, raising safety issues for the fall.

Thirty-four states have "no-excuse" absentee voting laws under which citizens either automatically receive ballots at home or can get them upon request.

The coronavirus effect:How much did it hurt Democratic primary turnout?

Voting by mail is most prevalent in the West. Five states – Colorado, Hawaii, Oregon, Utah and Washington – hold all-mail elections in which all registered voters are mailed ballots. More than two-thirds of voting in three other states – Arizona, California and Montana – is conducted by mail.

In 16 states, voters can receive mail ballots but only if they meet certain exceptions such as being 65 years or older, disabled or out of the county on Election Day and during the early voting period.

Republican governors in these states, mostly from the South, face an obstacle to expanding the process. Trump has slammed vote-by-mail, arguing that it undermines voter ID laws many Republican-controlled states championed and that implementing it on a national scale would hurt GOP candidates. "You'd never have a Republican elected in this country again," he said on Fox News.

Trump told a news briefing that he believes "a lot of people cheat with mail-in voting." A study by the Brennan Center found incidents of overall voter fraud "extraordinarily rare" – rates of 0.0003% to 0.0025%.

Several states oppose vote-by-mail expansion

In the 2016 election, Trump carried 11 of the 16 states that lack "no-excuse" absentee voting, and 11 are led by Republican governors.

In deep red Alabama, Republican Gov. Kay Ivey has repeatedly said she does not favor no-excuse absentee voting. “It raises the potential for voter fraud," Ivey said last month. "In the middle of a public health crisis, we don’t need to open that up and add another problem to our plate.”

Vote-by-mail advocates dispute claims of widespread voter fraud, noting that mail ballots rely on signature-verification tools to check voter authenticity.

Texas Gov. Greg Abbott, a Republican, told The Dallas Morning News he opposes mandating mail-in voting because it would infringe on the rights of people who vote at the polls. All states that mail ballots to all registered voters still allow for some form of in-person voting.

Texas, which has the second-most electors in the presidential election, has been targeted by Democrats as an emerging swing state because of its diverse electorate.

“I do not want to take away the law that provides the right of people to vote in person,” Abbott said, drawing accusations from Democrats that he wants to suppress turnout.

Warning sign:Wisconsin's messy primary shows struggles states could face in November election

A spokeswoman for Tennessee Secretary of State Tre Hargett, a Republican, said Tennessee is focused on the safety of elections officials and voters, but she expressed concerns about expanding vote-by-mail months before the election. Tennessee is among the states with strict voter ID laws that require photo identification to cast ballots.

"Tennesseans are in the habit of voting in person," spokeswoman Julia Bruck said, noting that only 2% of registered Tennessee voters typically cast absentee voters despite 30% being eligible.

She said election officials are preparing for "multiple scenarios" in November, including identifying available personnel and safety protocols. Bruck cited conversations with election officials from Washington state – one of the five all-mail states – who said at least five years is needed for states to transition to all-mail voting if they don't have 60% of voters voting by mail.

Secretaries of states disagree on feasibility

Bruck said Washington Secretary of State Kim Wyman, a Republican, warned Tennessee that "trying to flip the switch by November would be a heavy lift and could have catastrophic results.'"

Wyman, a source for multiple states amid the coronavirus outbreak for information about vote-by-mail expansion, was one of nine secretaries of state who joined Senate Democrats on a teleconference call to discuss voting during the pandemic.

"There really isn't a one-size-fits-all solution for the 2020 election," Wyman said, adding that as states expand absentee voting they must build in the capacity. "You've got to have the high-speed sorters. You have to have the relationship with the post office."

Jena Griswold, the Democratic secretary of state of Colorado, which adopted vote-by-mail elections in 2013, said it "tremendously increased access to the ballot" for millions of voters. Colorado leads the nation in the percentage of eligible regular voters, she said, and is among the nation's leaders in turnout.

"All eligible Americans should have the opportunity, just like Coloradans, to vote in accessible and secure elections. Americans' fundamental right to vote should not be dependent on the state we live in," she said. "And with federal support, it is feasible for every state to implement mail-ballot by 2020."

Griswold said most states aren't "starting from nothing," pointing to those that already have no-excuse absentee voting: "We have the foundation, and now we have to expand on it."

Two vote-by-mail critics on the same phone call disagreed.

Mac Warner, the Republican secretary of state of West Virginia, said a crisis is not the time to make sweeping changes. He said the state does not need "outside federal guidelines" and raised concerns about election fraud in vote-by-mail.

Kyle Ardoin, the Republican secretary of state of Louisiana, home to one of the nation's largest coronavirus outbreaks, said quickly ramping up to vote-by-mail is "neither prudent nor practical" in his state, where only 4% of voters vote absentee. He said it would be "riddled with numerous issues."

Florida is among the states where anyone can request an absentee ballot. After the state's primary March 17 – when absentee requests skyrocketed and same-day voting dropped – Florida's election chief concluded it is not equipped to issue mail ballots to all voters.

"Florida is not in position, at this time, to conduct an all-mail ballot election this year," Tammy Jones, president of the Florida Supervisor of Election, said in a letter to the state's Republican governor, Ron DeSantis.

Despite Trump, some Republicans open to change

Some Republicans said they support expanding vote-by-mail, given the circumstances.

"I support no-excuse absentee voting prior to the date of the election," Arkansas Gov. Asa Hutchinson said in a statement. "This is particularly important during this national health emergency. The legislature will need to amend the law or if the emergency continues then, as governor, I can act to assure voters have this additional way to safely vote."

Kentucky, a Republican-leaning state led by Gov. Andy Beshear, a Democrat, pushed its primary election back from May 19 to June 23, part of a joint agreement and executive order with Secretary of State Michael Adams, a Republican.

Though Adams campaigned against mail-in voting in his race last year, he indicated he is more open to the idea of expanding mail-in voting if the coronavirus persists much longer in Kentucky.

Adams testified in favor of a last-minute amendment to a revenue bill that passed through Kentucky’s Legislature that could give Beshear the power to move toward no-excuse absentee voting, if not all-mail-in voting.

"I ran during the campaign opposed to a vote-by-mail system, but I'm a realist," Adams said. "The most important thing for me is ensuring we have a free and fair election."

Kentucky:The coronavirus pandemic has the secretary of state thinking about mail-in voting

Democrats, from presumptive presidential nominee Joe Biden to Democratic National Convention chairman Tom Perez, have made vote-by-mail a rallying cry. But Democratic governors in states without no-excuse absentee voting have a long road to implementation.

"It makes all the sense in the world to me," Connecticut Gov. Ned Lamont, a Democrat, said about expanding absentee voting for the state's primary June 2. "I'm sort of navigating the politics around (the Capitol) right now on that issue. I don't want people going to a voting booth, I don't want them waiting in line. I surely don't want anybody over the age 60 or 65 in that position."

New York, hit especially hard by the coronavirus outbreak, faces constitutional hurdles to adopt vote-by-mail. Lawmakers passed legislation to begin the constitutional amendment process in New York for no-excuse absentee voting, but the measure needs approval by the newly elected state Legislature, which won't be seated until 2021.

Democratic Gov. Andrew Cuomo announced that all New Yorkers could vote absentee in the state's primary June 23, but he hasn't indicated whether he would take any additional steps for November.

In Delaware, as part of an emergency declaration by Democratic Gov. John Carey, social distancing is a valid reason to vote absentee in the state's primary June 2. Under normal circumstances, absentee ballots are limited.

“I know there’s concerns for a lot of individuals about the current environment with the pandemic happening,” Delaware Election Commissioner Anthony Albence told Delaware Public Media, adding that he believes the state can count the increased number of ballots in a timely fashion. Typically, only 5% of Delaware voters vote absentee.

A $400 million boost for elections included in the stimulus bill

Rallied by the chaotic Wisconsin primary – where some black communities most affected by the coronavirus outbreak had the longest lines at polls – civil rights advocates are stepping up their push for expanded vote-by-mail.

NAACP President and CEO Derrick Johnson called it "unconscionable" that many African Americans will have to choose between health and voting rights if action is not taken.

"The situation in Wisconsin is shameful and unacceptable, and we need to ensure this does not become the norm," Johnson said in an email this week to supporters.

If states do take action to expand voting options, major financial challenges would remain for implementation. As sales tax collections nose-dive because of stay-at-home orders, states face grim budget scenarios that would make an expensive endeavor even tougher.

That's where supporters of vote-by-mail say the federal government must step in.

The stimulus bill passed by Congress and signed by Trump had $400 million earmarked for election security amid the coronavirus crisis – far less than the up to $4 billion Democrats sought. The Brennan Center recommended $2 billion. States have wide latitude to decide how to spend their allocation of funds as long as it goes toward elections.

More:Trump weighs more stimulus checks for Americans. What else could be in next coronavirus aid package?

Danielle Root with the center-left Center for American Progress said she's hopeful about efforts in some states but called it "critical" to act quickly on vote-by-mail

"There's truly no time to waste," said Root, who serves as the organization's associate director of voting rights and access to justice. "One of the things, though, that states are having to contend with is that they do not have the budgets to do this, which is why Congress needs to allocate more funding."

One significant expense: Funds for states to include prepaid stamps for voters to return ballots – which Democrats want – in addition to postage to mail the ballots out. Not all "no-excuse" absentee states provide stamps. The American Civil Liberties Union sued Georgia on Wednesday over the issue, arguing that forcing voters to buy stamps to mail in ballots amounts to a "poll tax" and is unconstitutional.

A group of Democratic U.S. senators, led by Amy Klobuchar of Minnesota and Ron Wyden of Oregon, introduced the Natural Disaster and Emergency Ballot Act last month that seeks to ensure all voters nationwide can vote absentee and at least 20 days of early voting. The bill, which lacks any Republican co-sponsors, is a long shot to pass in the GOP-led Senate.

“We don’t see voting as a partisan issue," Klobuchar said during the conference call with the secretaries of state, adding that the nation must think "beyond the horror of the day" to start planning now.

Democratic leaders seek more funding for vote-by-mail in the next coronavirus relief package.

"It's about our democracy in a time where it's even a physical challenge to vote," House Speaker Nancy Pelosi, D-Calif., said this week on CNN. "So we want to have more resources for vote by mail, more same-day registration, more states sending ballots to those who are qualified to vote, that will be part of our initiative."

It's unclear where McConnell stands concerning legislation the Senate could consider. Although he backed the $400 million in the first bill, he has opposed Democratic efforts aimed at election security, saying he is against attempts to "federalize" elections.

On conservative radio host Hugh Hewitt's show last week, McConnell said, "I’m not going to allow this to be an opportunity for the Democrats to achieve unrelated policy items that they would not otherwise be able to pass."

Contributing: Christal Hayes, Joe Sonka, Bryan Lyman and Joel Ebert, USA TODAY Network, and New York state editor Joseph Spector

Reach Joey Garrison on Twitter @joeygarrison.