Professor at center of report that Russia hacked the election walks back his claim

Offering no evidence whatsoever, a group of computer scientists Tuesday night called on Democratic presidential candidate Hillary Clinton's campaign to challenge the election results in Wisconsin, Pennsylvania and Michigan — all states that President-elect Donald Trump  won — after suggesting  that Russians might have hacked voting machines in those states.

But now one member of that group, J. Alex Halderman, a computer science professor at the University of Michigan, is walking back those claims after reportedly contacting Clinton officials to notify them of their unfounded suspicions. The only evidence for their assertion is a "statistical analysis" that shows Clinton received 7 percent fewer votes in precincts that use electronic voting machines compared to those that use paper ballots.

While several media outlets ran with the story overnight and into Wednesday morning, Halderman published a blog post on Medium to offer some clarity about what he actually thinks happened — or didn't happen:

Were this year’s deviations from pre-election polls the results of a cyberattack? Probably not. I believe the most likely explanation is that the polls were systematically wrong, rather than that the election was hacked. But I don’t believe that either one of these seemingly unlikely explanations is overwhelmingly more likely than the other. The only way to know whether a cyberattack changed the result is to closely examine the available physical evidence — paper ballots and voting equipment in critical states like Wisconsin, Michigan, and Pennsylvania. Unfortunately, nobody is ever going to examine that evidence unless candidates in those states act now, in the next several days, to petition for recounts.

Regardless, the professor is still calling on the Clinton team to demand a recount because he is concerned about cybersecurity and has seen instances of hacking throughout the year, though he doesn't seem to believe Election Day is an example of such activity.

Later in the post, Halderman argued that it is very easy to install "vote-stealing malware" on electronic voting machines and described the fact that states independently run their own election operations, and decide their own voting methods, as a vulnerability. He argued paper ballots are the safest bet.

"The paper creates a record of the vote that can’t be later modified by any bugs, misconfiguration, or malicious software that might have infected the machines," he wrote.

At the end of the post, Halderman urged election officials to begin working immediately on increased security measures for the next big election.