The researchers work for the super PAC, American Bridge 21st Century, which is unveiling a new website on Friday called VeepMistakes.com. The site features more than 1,300 pages of opposition research and scores of video clips.

Political prognosticators can only speculate who is on Romney’s short-list, but now we know who the Democrats are preparing to target. The super PAC is shining their spotlight on three of the mostly likely contenders: former Minnesota Gov. Tim Pawlenty, Ohio Sen. Rob Portman and Florida Sen. Marco Rubio. Their research files, which the group is making public for the first time, also offers a sneak peek at the attacks the Democrats are poised to use against whichever potential V.P. ultimately gets the nod from Romney.

The American Bridge file on Portman, who has been the subject of more speculation than just about anyone else, runs nearly 350 pages. It includes sections on the Ohio senator’s legal career, his stints in prior presidential administrations and a rundown of his public statements on a raft of issues — from education to gun control to gay and lesbian rights.