Bernie Sanders is a hypocrite, "not a good boss," and "can't work with people to get things done," according to research prepared against him during the Democratic primaries by Hillary Clinton's campaign.
The extensive opposition research, or 'oppo,' was contained within a Nov. 5, 2015, email sent to Clinton campaign chairman John Podesta, which was published this week by WikiLeaks.
The hacking of Podesta's emails follows a wave of attacks on the email of prominent political figures and operatives that US officials have connected to Russia and Russian interest in influencing the election.
Many campaigns prepare research against their opponents, but the release of the documents comes as Democrats continue to try to unify in opposition to Donald Trump after a bruising primary battle between Clinton and Sanders.
The 2015 email, from Clinton research director Tony Carrk, included six attachments, containing more than 1,000 pages of research on Sanders, who at the time was rising in the polls.
One of the documents, called "Sanders Top Hits," included a lengthy section on the Vermont senator's "bad record on guns," an issue on which Clinton would repeatedly criticize her opponent during the primaries.
The document also includes sections describing him as being "at odds" with key Democrat constituencies, including women, black people, Latinos, and the LGBT community.
"While claiming be a champion on issues of equality, Sanders has not been a leader on issues most important to women, African Americans and Latinos, and has said that issues of race and gender were secondary to the class struggle," reads another document.
"Sanders has evolved on numerous issues," reads another section, that details his positions on marriage equality, drugs, and the legal liability of gun manufacturers.
Another section accused him of taking past "extreme" positions on taxation and drug legalization.
