Hackers may try to stir up trouble but will likely have little impact on U.S. election results

Cyberattackers who have caused all sorts of trouble in the U.S. election campaign could attempt to wreak significant electoral havoc this Tuesday.

But some experts suggest that while there are opportunities for hackers to engage in mischief making, it's unlikely they would be able to infiltrate the actual electronic voting machines millions of voters will use to cast their ballots.

"The chances that the actual ballot tabulation could be hacked are next to nothing," said Michael Cornfield, an associate professor at George Washington University's Graduate School of Political Management and Research. "It's almost impossible."

'The Russians have a motive to discredit American democracy. And the opportunity is this election.'- Herb Lin, senior research scholar, Stanford University

Still, some experts say Russia which has been blamed for two significant email hacks this campaign, will do what it can to try to discredit the U.S. electoral process on Tuesday night.

"Who has the means, the motives, the opportunity? Certainly, Russia has the means," said Herb Lin, a senior research scholar at Stanford University's Center for International Security and Cooperation. 

"Who has the motive? The Russians have a motive to discredit American democracy. And the opportunity is this election."

Decentralized system makes tampering unlikely

When it comes to the voting machines, the fear is that hackers could tamper with them in a such a way, for example, as to make a vote for Democratic presidential candidate Hillary Clinton count as a vote for Republican presidential candidate Donald Trump.

But that would be extremely difficult as the U.S. has such a decentralized voting system with over thousands of jurisdictions.

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"I think it's least likely because there are thousands and thousands of polling machines that you would have to get at," Lin said. "Not impossible but really hard to do."

According to Martin Libicki, a cyberwar expert at the RAND Corporation and author of Cyberspace in Peace and War, hackers will also be thwarted by the fact that the voting machines aren't connected to the internet, and there's not a lot of internet voting taking place.

However, that's unlikely to stop Russians from trying to meddle in the election in some way, said James Lewis, an expert in cybersecurity at the Washington, D.C.-based Center for Strategic and International Studies.

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Russia-linked hackers might try to mess with voter registration databases, which are online, and remove voters from the list. 

Lewis pointed to the state election websites in Illinois and Arizona that experienced hack-related shutdowns earlier this summer. In both cases, the parts of the websites affected involved online voter registration.

Hackers can undermine trust in system

"[Hackers] can't change the outcome, but they can do things to make the election look like it had problems," Lewis said.

They have already played a role in the campaign. In July, thousands of emails from the Democratic National Committee were released by WikiLeaks — emails that some security experts believe were hacked into by cyberattackers with links to the Russian government. 

And just recently, another leaked email hack, this one targeting top Clinton campaign aides, was also attributed to Russian operatives by some analysts. 

"It wasn't an intelligence operation; it was a political operation," Lewis said. "It's what the Russians call active measures. They've gone out of their way to discredit the electoral process."

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That could also be achieved, Lin suggested, if hackers attempt to mess up the election results data or access to that data, which is used by media when making election calls for states.

"It doesn't have legal significance, but it adds to the chaos and gives people a lack of confidence in what's going to happen."

Russia has denied all claims that it was behind the email hacks and has accused Republican candidate Donald Trump and Democratic candidate Hillary Clinton of blaming Russia to score political points.

Get-out-the-vote efforts could be affected

Cornfield said hackers may have the most luck at infiltrating the private computer systems of the respective political parties and hampering their get-out-the-vote efforts.

For example, they could sabotage parties' efforts to organize volunteers to give people rides to the polling stations, he said.

Even though no actual disruptions are likely to occur, that doesn't mean that certain people won't allege they will occur.- Michael Cornfield,  associate professor, George Washington University

The computers that the parties use are not publicly audited like official election computers, making them more vulnerable to attack, Cornfield said.

Cornfield still thinks it's an unlikely scenario, but even if hackers were able to break into those systems, he said, it wouldn't mean it would happen in the entire state, or that it would have a significant impact on the results of the entire election.

"Even though no actual disruptions are likely to occur, that  doesn't mean that certain people won't allege they will occur," he said. "In the category of perceptions that the election is rigged, we have unprecedented troubles ahead."