Some Mexican immigrants in North Texas are finding out they can’t register to vote in Mexico's July presidential election even though the deadline is more than a week away on March 31.

Potential voters are being scheduled for appointments to fill out their registration paperwork, but those appointments are now being scheduled for April and beyond — after the deadline to register to vote in the presidential election.

For the first time in a presidential election, Mexicans can register from outside their homeland to vote absentee. In the past, they had to go home to register.

The change has left Mexican consulates around the U.S. swamped. By mid-March, more than 615,000 Mexicans living outside Mexico had already begun the registration process. The North Texas diplomatic post has already started the process for about 67,400 registrants.

More than 10 million Mexican-born immigrants in the U.S. are over the age of 18 and, therefore, eligible to register to vote, according to U.S. Census Bureau data.

There are too many voting applicants for the consulate in Dallas to process in time for the presidential election.

“We offer what we have and that’s 500 appointments a day," said Francisco de la Torre, the Mexican consul general in Dallas. "We don't have more to offer."

The deadline of March 31 was set by the National Electoral Institute of Mexico and can't be changed, said de la Torre, a big proponent of voting rights for Mexicans abroad. The consulate will have extended hours on Saturday, March 31, to handle the applicants who have appointments.

"I am very proud that we are number two in the United States, after Los Angeles and before Chicago," de la Torre said.

But in Dallas, an unknown number can't get the appointments they need to register in time for the presidential election. It’s unclear how many other consulates may have similar registration backlogs.

Carlos Gonzalez-Gutierrez, the consul general in Austin, said that no more appointments were available this week at his consulate but that officials there were still doing what they could to register voters.

“We have zero availability for this week, but next week we still have plenty of room,” Gonzalez-Gutierrez said.

Contentious elections

The election is expected to be close and contentious. Votes from abroad could play an important role. In 2006, the reported margin of victory was about 244,000 votes, meaning the U.S. tally could be critical.

The importance of the more than 600,000 potential Mexican voters living outside their homeland has been reflected in the unusual sight of at least one candidate for the Mexican presidency visiting the U.S. this year.

Andres Manuel Lopez Obrador, a leftist, was defeated in his bid for Mexico's top post in that 2006 election and is running again. Polls have the 64-year-old as the front-runner with a double-digit lead over 39-year-old Ricardo Anaya, who is running with a right-left coalition. Anaya visited California a few weeks ago.

The ruling party candidate, Jose Antonio Meade, though embraced by many in the business community, is in third place in the polls. The 48-year-old Meade served in the Cabinet of the current president, Enrique Pena Nieto.

U.S.-Mexico relations are a prominent theme in the election because of President Donald Trump’s demand that Mexico pay for a border wall, as well as his tougher immigration policies and his intention to recast the 1994 North American Free Trade Agreement.

"People need to vote. This is worrisome. This is not in support of democracy," said Guadalupe Correa-Cabrera, a political scientist at George Mason University and a fellow at the Mexico Institute at the Wilson Center in Washington, D.C. "The elections can get very close. In presidential elections, it's usually a race of two, particularly in this election. Lopez Obrador is winning the polls with 10 percent, but things can change substantially."

Correa-Cabrera said the Mexican government should increase consular staffing so all who want to register may do so.

To start the registration process, Mexicans have to request an appointment by calling 1-877-MEXITEL. But if they call now, they will be getting appointments beyond the March 31 deadline for the presidential election, said Ruben Ovando, spokesman for the Mexican Consulate in Dallas.

“The registration process began on February 8, 2016, and on March 31 we will be working extra hours between 8 a.m. and 10 p.m. to process the last 450 appointments” to get voting credentials for July 1, Ovando said. But that will be to process people who’ve already gotten the critical appointments to register to vote.

¿Cómo votar desde el extranjero? Aquí te decimos 👇🏽

⚠️Recuerda: Solo tienes hasta el 31 de marzo para registrarte: https://t.co/2LhNmUZX5F #Elecciones2018

México está donde estás tú 🇲🇽 pic.twitter.com/AgJixCzF4W — Voto Extranjero (@VotoExtranjero) February 13, 2018

“The deadline is not in our hands. It’s established by the National Election Institute,” said Ovando, who saidt his office was working as hard as it could.

Mexicans who get the appointments to register are given a card that they must activate with a phone call — just as with a credit card — to get their ballot mailed to them. Then they have to send the ballot to election officials free of charge by courier service.

At an election forum at the Mexican Consulate in Dallas on Friday, Socorro Perales said she was frustrated to learn she couldn’t get an appointment until April, too late to vote in the presidential election.

She went to the forum with her Mexican citizenship documents in hand, hoping to be able to register if she showed up in person rather than making a phone call.

“Mexicans on this side could actually turn an election,” said Perales, who holds U.S. and Mexican citizenship and returns to Guanajuato about three times a year. “Mexico is a very special place for us.”

Perales said the vote abroad had been marketed by the Mexican government as an easy 1-2-3 process.

“You activate your card. Then, magic: You vote in Mexico. Well, it’s not like that at all,” she said. “It shows they don’t really care about us.”

Staff computational journalist Allan James Vestal contributed to this report.