Voting machines around the United States are coming to the end of their useful lives. Breakdowns are increasingly common. Spare parts are difficult, if not impossible, to find. That could be a serious problem for next year's presidential elections.

Allen County, Ohio, election director Ken Terry knows how bad things can get. In the last presidential election, he had to replace the Zip disks — a 1990s technology — in the main machine his county uses to count votes. The disks are no longer made. And when he finally got some from the voting machine manufacturer:

"They actually had a coupon in them. They were sealed and everything. And the coupon had expired in ... 1999," he said.

And, to make matters worse, Terry said his voting machines use memory cards that hold only 250 megabytes of data — a tiny fraction of what you can store today on a $6 thumb drive. "You know, by today's standards that's just absurd," he said.

Allen County is by no means alone in dealing with antiquated voting equipment. In Michigan, optical scan machines purchased in 2005 are breaking down at an increasing rate. That can be frustrating for voters and election workers, Oakland County election director Joe Rozell said.

"We've all become experts with cans of compressed air, trying to clear any debris or any pieces of paper that may have jammed the ballot path," he said.

Michigan is trying to get new machines for next year's elections. But that's not the case in Ohio or most other states with aging equipment. According to a new report by the Brennan Center for Justice at New York University, 43 states will use some voting equipment next year that's at least 10 years old.

"We're not saying that all the systems are going to fail on Election Day — most systems will work. But the closer you get to this end of projected lifespan, the more likely you're going to see problems," said Larry Norden, one of the report's authors.

Problems such as vote flipping — that's when a voter presses one candidate's name only to have the opponent's name light up. It happens when the glue on touch-screen machines gets old and erodes. Norden said everything's coming to a head at once because almost every state bought new computerized voting equipment right after the disputed 2000 election, using $2 billion in federal aid. But he says now there's neither the money nor the same sense of urgency.

"More than one official has said to me [that] legislators [and] county funders are waiting for a disaster, which I think is crazy," he said.

Disaster does seem increasingly possible. Earlier this year, the state of Virginia realized that machines used in 20 percent of the state were vulnerable to hackers and immediately ordered them replaced.

"It's not a cheap endeavor. You know, we're talking probably $10[,000] to $12,000 a precinct," said state election commissioner Edgardo Cortes. That means hundreds of thousands of dollars for some counties, he said.

He worries that while rich counties will be OK, poorer ones will struggle — especially after the Legislature rejected the governor's request for $28 million to buy new voting equipment statewide.

Some local governments, he said, just "can't afford at this point to put out that kind of money."

And the Brennan Center found a similar pattern in other states, where wealthier counties are getting new equipment, while poorer ones are not.

Cortes and other election officials said they're not really worried about losing votes — most systems have paper ballot backups — but they do worry about maintaining voter confidence if broken machines mean longer lines and confusion at the polls.

Cortes said voters need to be confident "that the democratic process is working and that elections are as easy as possible to participate in for all our eligible citizens."

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