With growing evidence that Russia is meddling in the US presidential election—allegedly by hacking the Democratic National Committee and releasing embarrassing emails—the concern that somebody might try to hack voting machines no longer seems outlandish. And as many as one-fifth of all votes cast in the November election could be particularly vulnerable to interference. … Concerns about the vulnerability of the country’s voting infrastructure are mounting just as Republican nominee Donald Trump has begun talking about howthe election might be rigged against him. The absence of a paper trail on millions of ballots in swing states could give Trump plenty of ammunition for his conspiratorial allegations—and make them virtually impossible to disprove. “You really want to have a baseline of evidence that you can use to demonstrate that the outcome [of an election] was correct,” says Pamela Smith, president of Verified Voting, which pushes for accurate, transparent, and verifiable elections. “The DNC hack takes this idea out of the realm of the theoretical and into the ‘Oh, this could actually happen.'”