This November, West Virginia will be the first state to allow voters to submit federal ballots via a smartphone app that relies on the “blockchain” technology behind cryptocurrencies like bitcoin, along with a selfie video, all in a bid to thwart Russian hackers.

But the first-of-its kind pilot program, originally designed for military serving overseas, has sharply divided the tech community between supporters who say it represents the future of secure elections and critics who argue it does little to fix the problems inherent in online voting.

For November’s midterm elections featuring one of the premier Senate fights of the cycle, the stakes for an accurate count in West Virginia could not be higher.

Democratic incumbent Sen. Joe Manchin is running neck-and-neck with challenger Republican Attorney General Patrick Morrisey, in what pollsters say will help decide who controls the Senate next year.

The state’s open 3rd Congressional District seat could also be critical in which party gains a majority in the House, with Republican State Delegate Carol Miller and Democratic state Sen. Richard Ojeda squaring off in what local observers call a toss-up.

West Virginia was not among the 21 states that Russians attempted to hack during the 2016 election, according to intelligence officials, but neighboring Ohio, Pennsylvania and Virginia were. With U.S. intelligence agencies predicting that the Kremlin will again attempt to interfere in the 2018 vote, election security officials are understandably on edge.

Richard Stroupe is the CEO of Sequoia, a D.C.-based tech developer that works on blockchain applications for the national government. He acknowledges that the technology is still in its infancy and has perception challenges because of its connection to the shadowy cryptocurrency bit coin.

“But in terms of improving security for election,” Mr. Stroupe said, “blockchain opens the door to hundreds of solutions.”

West Virginia’s service members serving overseas are hoping those solutions address timeliness and anonymity, two problems state election officials have identified with the absentee ballots they cast.

Overseas absentee ballots must be mailed and reach state election offices by Election Day. This caused a major problem in 2016, according to the U.S. Election Assistance Commission. Nationwide, officials rejecting roughly 19,000 such absentee ballots because they arrived late.

A driving force behind West Virginia’s blockchain initiative was Republican Secretary of State Mac Warner.

Mr. Warner was stationed overseas for the 2012 presidential election serving in the Army’s Judge Advocate General Corps. He was unable to vote because he lacked reliable mail service or a fax to send his absentee ballot home.

To tackle the issue, he worked with a Boston-based tech firm, Voatz, which ran the blockchain pilot program during the state’s primaries in May. It requires a voter to register by taking a photo of their government-issued identification and a selfie-style video of their face.

According to Voatz, facial recognition technology then verifies the identity and allows the vote to be cast. The pilot worked in two West Virginia counties and now all 55 counties can access the program.

The Voatz program has deeply worried some election security experts, like Mike Orcutt, an associate editor of the MIT Technology Review and cryptocurrencies and blockchain expert. Many in the cybersecurity community feel blockchain — and the overall idea of online voting — is “fundamentally insecure” and far more dangerous than paper balloting, Mr. Orcutt wrote recently. Computers, phones, and other devices can all be hacked, he and others argue.

“Protecting connected devices against hacking is hard enough, and, even if that could be achieved, developing an online system that preserves all the attributes we expect from democratic elections would be incredibly difficult to pull off,” Mr. Orcutt wrote.

Voatz and Mr. Stroupe insist that blockchain is exactly the solution that is needed because the technology distributes data over what its practitioners call the ledger, or a massive number of “blocks.”

“Blockchain, by its nature, is almost impossible to hack,” Mr. Stroupe said.