“Make sure to confirm that your summary page accurately reflects your choices BEFORE casting your ballot!” reads a flier distributed by the Texas secretary of state’s election division to state polling locations.

The notice was the agency’s quick fix for a glitch in its widely used Hart eSlate voting machines.

Texas native Peter Martin, 69, was one of many who missed the message.

“I’ve always voted. It’s the only opportunity that I have to make any sort of difference in terms of politics,” he said.

When the registered independent went to a recreational center in Grapevine, Tex., last week, he planned to vote for Senate hopeful Beto O’Rourke. The Hart machine offered a fast-tracked option for straight-ticket voters. Martin selected it, expecting the machine to populate an all-Democrat ballot.

“It floored me. My vote showed up on the machine for the wrong senator. Instead of Beto O’Rourke — the Democratic candidate — it said [Republican candidate] Ted Cruz,” he said. After noticing the error, Martin backtracked to the initial screen and manually registered his vote.

The Texas secretary of state has been aware of the issue for at least a week.

An election advisory from Director of Elections Keith Ingram, dated Oct. 23, said: “We have heard from a number of people voting on Hart eSlate machines that when they voted straight ticket, it appeared to them that the machine had changed one or more of their selections to a candidate from a different party. This can be caused by the voter taking keyboard actions before a page has fully appeared on the eSlate, thereby de-selecting the pre-filled selection of that party’s candidate.”

Martin denied misusing the machine. “What is this going to be, another Dade County?” he said, referring to disputed Florida ballots in the 2000 presidential election. “The only vote that counts with national scope is the one being destroyed.”

Hart Intercivic, the machines' maker, released a statement in which it said it “proudly stands behind our voting systems and our customers,” also praising election officials.

Marian K. Schneider, president of Verified Voting, a voting integrity organization, issued a statement Monday in response to reports that voters experienced problems using the company’s machines. She called for verifiable systems that include a voter-marked paper ballot: “Verified Voting calls on Texas Secretary of State Rolando Pablos to launch a broader and more robust statewide public information effort to advise voters to carefully check their choices as displayed before submitting them. … Paper ballots that are retained can be later sampled to check if the software is correctly reporting the voters’ selections. Without such a safeguard, public confidence in elections diminishes.”

The issue, she said, impacts 5.1 million Texas voters, at a minimum.

Pablos said in a news release Saturday that the machines are working.

“It is important for all voters in the 78 Texas counties utilizing the Hart Intercivic eSlate to understand that the voting machines are not malfunctioning, nor are they arbitrarily “switching” the choices of voters who cast a straight-party ballot,” he wrote.

The state has had problematic run-ins with the Hart voter systems in the past, said Sam Taylor, communications director for Pablos. She also confirmed that voters in only five counties had experienced issues with the machines.

During the 2016 election, the agency ran tests on the machines after voters’ choices of presidential candidates were deselected. The problem affects only the first race on the ballot. In 2016, that was the presidential race. This year, it’s the senatorial contest.

The diagnosis then was that voters were using the selection wheel before the screen finished rendering, Taylor said.

As a result, the office has provided additional signs and held training and annual election law seminars for Texas election administrators with voting machines. Pablos reemphasized Saturday that “county election officials are properly performing their duties and have been properly advised and trained to assist Texas voters.”

There have been fewer than 20 complaints, Taylor said, and all those affected were able to recast their votes for Senate after discovering the glitch. However, hundreds of Texans might have cast early ballots or failed to double-check before submitting.

The Texas Civil Rights Project reported receiving about a half-dozen complaints, the Texas Chronicle reported. Of them, most were straight-ticket votes for Democratic candidates that appeared in error for Cruz. One was a Republican straight-ticket ballot that tabulated for O’Rourke.

Since the Help America Vote Act of 2002, about 200 Texas counties purchased voting machines; dozens have since updated their equipment, Taylor said. Of the 254 Texas counties, 82 use the Hart eSlate machines.

Correction: An earlier version of this article misidentified Verified Voting as the maker of the Hart machines.

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