(POLITICO) — Hackers could influence the outcomes of November’s elections, a computer science professor who has demonstrated security weaknesses in voting machines told lawmakers on Wednesday.

“It’s possible,” said Andrew Appel, a professor at Princeton University, at a House Oversight IT subcommittee hearing focused on election cybersecurity.

But Appel, who has hacked voting machines used in many states, was the only one to reply affirmatively when subpanel Chairman Will Hurd (R-Texas) asked for a “yes” or “no” answer to the question, “Can a cyberattack change the outcome of our national elections?

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