However, the researchers found that many of these tweets were generated by bots: Automated Twitter accounts programmed to send out tweets. The most active bot accounts can make more than 500 or even 1,000 tweets a day.

Analyzing 9 million tweets following the first presidential debate and 11.5 million tweets after the second debate collected from 2 million users, a team of researchers from Oxford University, Corvinus University and the University of Washington found the amount of traffic in pro-Trump hashtags was roughly double the activity in the hashtags of his Democrat rival Hillary Clinton. During the debates themselves, around 40 percent of tweets included pro-Trump hashtags, as opposed to 12 or 13 percent using pro-Clinton hashtags.

Twitter seems to be heavily in favor of Republican presidential candidate Donald Trump , but a sizeable slice of his support comes from social media bots, according to new research.

"The accounts using a high level of automation—the accounts that tweeted 200 or more times with a related hashtag and user mention during the data collection period—generated close to 25 percent of all Twitter traffic about the presidential debate," the researchers – which include Philip Howard, a professor at Oxford University - said in the new report published Wednesday.

"It is difficult for human users to maintain this rapid pace of social media activity without some level of account automation, though certainly not all of these are bot accounts."

The report did not speculate on the sources of these bots, so it is unknown who controls them.

According to the report, automated pro-Trump accounts generated four tweets for every tweet from a highly automated pro-Clinton account. In addition, about one third of the pro-Trump traffic on the social media website Twitter was driven by bots and highly automated accounts, compared to one quarter of the pro-Clinton traffic.

"Pro-Clinton highly automated accounts increased their activities from the first to second debate but still never reached the level of automation behind pro-Trump Twitter traffic," Howard told CNBC via email.

Using bots to flood support for one candidate or the other on social media is part of a troubling trend to distort public opinion, the researchers said.

"Political actors and governments worldwide have begun using bots to manipulate public opinion, choke off debate, and muddy political issues," the team said. "Political bots tend to be developed and deployed in sensitive political moments when public opinion is polarized."

The media representatives for Donald Trump's presidential campaign were contacted but were not immediately available for comment.

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