Texas this week will preview the sharp divergence that may lie ahead as the Republican and Democratic parties grapple with the impact of the coronavirus pandemic on the 2020 election.

The Texas Democratic Party has transformed its state convention this week into an entirely online event, complete with speeches from presumptive Democratic nominee Joe Biden and other top party leaders and an unprecedented effort to conduct virtual training for volunteer organizers.

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Meanwhile, the state Republican Party is steaming ahead with plans for a completely in-person convention in Houston in July that will not require the wearing of masks, according to Texas GOP Chairman James Dickey.

The contrasting approaches may foreshadow the differences approaching as national Democrats openly consider whether to move their Milwaukee convention partly or entirely online and three Republican officials told CNN that President Donald Trump will not accept the nomination in Charlotte, North Carolina, after the state's Democratic governor on Tuesday would not budge from his demand that GOP leaders provide him with plans for a scaled-down convention there that includes face masks.

While national Democrats say they have made no final decisions on their convention's format, Trump and the Republican National Committee set a deadline of Wednesday for North Carolina to respond to his demands for an unfettered in-person gathering. Late Tuesday, after the governor's response, the President tweeted that the GOP will be "forced" to find a new state -- though the RNC must hold some events in Charlotte because of contractual agreements, and the decision apparently isn't yet final.

Some smaller state Democratic parties (including in Maryland and Maine) have already held virtual conventions, but Texas is the largest state to do so.

"Because of the ongoing pandemic ... the entire Democratic infrastructure has their eyes on this," says Abhi Rahman, the Texas Democrats' communications director. "Everyone in the Democratic Party recognizes this is the first run at this scale."

Protests that have spiraled at times into looting and violence in major cities across the country since the death of George Floyd in Minneapolis last week have only underscored the questions surrounding Trump's drive to preserve an in-person convention. A gathering to nominate Trump in an increasingly Democratic city could be a magnet for volatile protests, especially after he's pressed governors to use force more aggressively to quell unrest.

Reinventing the convention

The Texas Democratic gathering, which began Monday, will also mark an important milestone in the effort by Democrats and allied groups to shift their voter registration and turnout efforts online. New voter registrations across a wide variety of states plummeted by as much as two-thirds in March and April compared with the same period in 2016, according to figures collected by TargetSmart, a Democratic voter targeting firm.

Now, like other state parties and allied liberal groups, the Texas Democrats are mounting a major effort to restart their registration efforts through digital means. But all of these groups are building new operations on the fly, and voter turnout experts agree it will be difficult for them to reach as many potential new voters as they planned before the pandemic.

Republicans in Texas and elsewhere will face similar challenges. But the hurdles may be especially stubborn for Democrats, who have traditionally relied more on in-person organizing, and who are also targeting low-income communities that may be less reliably connected to the internet.

"Admittedly, this is a huge undertaking," says Luke Warford, the Texas state party's director of voter expansion.

Texas Democrats had initially planned to host their convention in person in San Antonio this week, attracting about 12,000 people. But when Bexar County, which contains San Antonio, issued guidance against large-scale public gatherings, the party quickly switched to a virtual event. Party officials found few precedents for planning an online event at such a magnitude.

"We had some conversations early on with other state parties," said Hannah Roe Beck, the party's convention director. "I remember a phone call and I took eight pages of notes, as we all shared broadly what we were thinking and planning. I don't think anybody has done what we are doing at this scale."

The convention's core will be online broadcasts on Facebook, Twitter, YouTube and a state party website of general sessions on Friday and Saturday. In a reflection of Democrats' growing confidence about again contesting Texas -- after a quarter century of nearly complete Republican dominance -- the event is attracting an A-list speaking roster including Sens. Elizabeth Warren of Massachusetts and Kamala Harris of California and House Speaker Nancy Pelosi of California.

Brittany Switzer, the Texas Democrats' senior brand director, said the biggest challenge in moving online "was making sure that our guests and our delegates still had the same experience with the show programming. How can we bring that element of the pep rally of the convention online?"

For ideas, Switzer said, she looked to other large-scale digital events, including video gaming tournaments and the South by Southwest festival held annually in Austin. The party's answers included:

Building a digital platform that makes it easier for the many caucuses and candidates to hold virtual meetings with convention attendees on Facebook Live or Zoom.Filming short video messages that will play throughout the program encouraging attendees to volunteer for organizing work or to contribute to the party.Establishing "virtual media rooms" in which reporters can question speakers after their remarks.Encouraging speakers to have their campaigns communicate extensively with viewers through the chat functions that will be available during the online broadcast.

Switzer says the party believes this virtual event may even represent an improvement in the traditional in-person convention because it will allow a broader circle of people to participate, including many who could not have traveled across the sprawling state to attend a live gathering.

"These systems really have opened up our convention to the public in ways that we wouldn't necessarily have been able to do before," she says. "Now it is all online and everyone can participate."

Texas GOP expects fewer changes

The contrast could not be starker between any of this and the convention plans of Texas Republicans. Other than delaying the date from May to July, the Texas GOP is expecting relatively few changes for its state convention in Houston.

"We are moving forward with an in-person convention in Houston in the middle of July as planned," said Dickey, the state GOP chairman. "We moved it to July to give us plenty of time to figure out how to do it well and safely, and we are comfortable that we have done so."

Dickey says the party has altered its plans in some ways. "We have acquired additional space and we have changed up the seating plans for the rooms to allow for more distance between participants," he says. "We have arranged for a significant number of hand sanitizer stations that was not at all on the original plan."

But the party will not mandate that attendees wear face masks, Dickey says. "We do not currently have any intention to require masks," he said. "We do encourage anyone who feels the desire to wear one for their own sake or for the benefit of others to do so and we expect everyone to support their choice to do so."

Nor is the GOP working to reduce the number of people attending, he said, though he expects that concerns about the virus will nonetheless keep down the crowd to about 7,500. Previous conventions have drawn from 5,000 to 12,000 attendees, he said, though the party expected that the strong attachment Trump generates in his supporters might have otherwise swelled that to as many as 15,000 this year.

While Dickey said he is confident the GOP can hold the event "safely," Rahman charges that the gathering will endanger local workers in Houston.

"The fact is what they are doing is going to put Texans at risk," he said. "It's going to put the workers at risk; that's the worst part of this. ... It goes back to how Republicans have been treating this coronavirus crisis since day one, especially down here in Texas."

Texas contrast mirrors national parties

These arguments undoubtedly preview the competing claims likely to emerge this summer as national Democrats likely shift some or all of their planned Milwaukee convention online and Trump insists that the GOP hold a full-scale in-person event.

Trump told North Carolina's Democratic Gov. Roy Cooper last Friday that he would not reduce the size of the event or accept requirements for mask-wearing; over the weekend, the Republican National Committee wrote state officials that the convention would require hotels and restaurants, which are now restricted in the state's graduated reopening plan, operating at full capacity.

Dickey said that just moving the Texas state convention back a few weeks in the same city required "a herculean effort." But he said officials in at least two of the state's major cities -- he wouldn't specify which -- privately told him they would welcome the national Republican convention if Trump withdrew it from Charlotte, despite all the logistical challenges involved.

"If anyone can pull it off, Texans and the RNC and the Republican Party of Texas could pull it off," he said.

The contrasting convention blueprints are only one measure of how differently the parties are adjusting to the pandemic in Texas, a state that is drawing the most national political attention in years. Republicans have dominated the state since George W. Bush beat tart-tongued Democratic Gov. Ann Richards in 1994 and Trump carried it by just over 800,000 votes in 2016. But Democrats have been energized since then-US Rep. Beto O'Rourke cut that deficit to just 215,000 votes in his Senate loss to Republican incumbent Ted Cruz in 2018.

"Since 1994 -- when Ann Richards lost -- every year, whether it was the midterm or the presidential, people would start to feel more disheartened," said Lydia Camarillo, president of Southwest Voter Registration Education Project, a group that registers Latino voters. "Then people got excited about Beto and ... [now] the difference is dramatic."

Energized Democrats recast Texas voter push

Texas has one of the nation's largest pools of unregistered voters (about 5.5 million of the state's roughly 21.5 million eligible voters) and most of them are either young or people of color, Warford says. (Fully two-thirds of the 1.7 million Texans who have turned 18 since 2016 are nonwhite, according to calculations by demographer William Frey from state data.) The state Democratic Party initially set a goal of registering 2 million new voters this year, the most it had ever signed up.

As with the convention, the pandemic forced the party to redraw those plans. While it initially planned to sign up most of those new voters through in-person contacts such as door-knocking, it now hopes to register half of them through a new English- and Spanish-language website it established called RegisterTexas.com.

Adding to the challenge, Texas has some of the nation's most restrictive voter registration laws. It does not permit online registration, so the party is sending people who provide their information to the website filled-in applications that the voters can sign and return to the state in prepaid envelopes.

"We wanted to get as close to online registration as possible," said Warford.

That's just one hurdle for voters to participate in Texas. Most attention has focused on the legal efforts by state Republican Attorney General Ken Paxton to bar voters from mailing in ballots because they fear contracting the virus if they vote in person. But Texas also has a stiff requirement that anyone registering voters must be certified by the county that they are working as a so-called "volunteer deputy registrar."

The county training sessions to receive that certification have been disrupted by the outbreak, so in another digital advance, the state party has worked with officials in Travis County (which includes Austin, the state capital) to hold a first-of-its-kind online training session on Saturday morning that it hopes will attract 1,000 volunteers.

Warford said it's impossible to guarantee today that the party will send out such volunteers to do in-person registration, or get-out-the-vote activities, before the election.

"Of course, if the public health situation allows it, I would love to be able to register voters in person," he says. But, he added, "I think the reality is I can't tell you."

Camarillo of the Southwest Voter Registration Education Project likewise says the group -- which is famed for its extensive in-person local organizing -- can't guarantee it will return to in-person activity before November.

"Our strength has been grassroots," she said. "Well ... we know that even if you have a mask and you are 6 feet away that doesn't mean you are not going to catch [the virus]. We have to be very careful how we work so staff ... and volunteers are safe, and voters stay safe."

Again, the contrast with Texas Republicans could not be starker. The state set a relatively modest goal of registering 100,000 new Republican voters, primarily by recruiting GOP volunteers to contact unregistered potential Republicans by phone or text; Dickey says the party has already signed up almost 90,000. "That process was nearly ideally suited for lockdown," he says.

As for activities this fall to mobilize voters to turn out on Election Day, Dickey says the party has not altered its plans. Texas Republicans, he said, "absolutely" plan to contact Trump supporters through door-knocking and other in-person contacts.

"Texas will be back to work," Dickey told me. "Texas is opening, and all of Texas will be back to work long before November, including political effort."

This story has been updated with further developments on the Republican National Convention.