ABP-8201 Scandal KeyArt.inddABC‘s D.C. fixer drama Scandal has built big ratings in three seasons with a potent mix of often ridiculous plot twists and creator Shonda Rhimes’ savvy use of social media, which has bound fans closely to the show and its stars. That combo has paid off: Ahead of tonight’s season finale, which is certain to feature another signature shocker, Scandal has added 3 million viewers (for 11.5 million total). It’s up even more in the key adults 18-49 demo, +43% compared with last season, according to Nielsen. That demographic also represents most of the heaviest social-media users and is fervently sought by marketers.

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Scandal table with red borderScandal‘s OMG moments, and the chance to feverishly chat about them online as they happen, have glued fans to the show’s actual broadcasts, instead of waiting to watch an episode later on DVR, VOD or Hulu. To further stick fans to their TV-side seats, Rhimes and other show principals including star Kerry Washington also take part, tweeting and posting with fans before, during and after airings. That close connection has been a crucial part of the show’s growth. According to RelishMIX, the social-media analytics firm, followings for those show-connected accounts have exploded — led by Washington’s Facebook account, which jumped an eye-popping 466% in Season 3. That comes after an offseason filled with awards appearances that really fueled the show’s social-media growth. In fact, says RelishMIX CEO Marc Karzen, the biggest growth in Washington’s Facebook account happened in and around her (very pregnant) appearances at the Golden Globes and SAG Awards. Those red carpet photos set fans abuzz for days.

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The growth hasn’t just been in the official accounts either. RelishMIX tracks what it calls the Social Media Universe for TV shows and films on YouTube, Facebook and Twitter. It looks not only at the official accounts connected to an entertainment property and its principals but also at those superfans who post regularly and often create show-themed online content such as fan fiction, GIFs and detailed plot postmortems. In Scandal‘s case, that often can include video breakdowns of every lingering kiss and KERRY WASHINGTONcaress between Washington’s character and her secret lover/former boss (Tony Goldwyn), who also happens to be the U.S. president. As the RelishMIX graphic shows, Scandal has really taken off on Facebook and (especially lately) Twitter. The show also has attracted an ardent (and sometimes quite critical) fan base on Tumblr.

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Karzen said Rhimes’ production company Shondaland has been effective in using social media to support both Scandal and Grey’s Anatomy, Rhimes’ other, older Thursday night drama on ABC. Scandal is now fourth among ABC dramas in social-media engagement, and 12th among all networks’ dramas. “How do you drive social engagement for a show?” Karzen asks. “Go to ‘Shondaland Social Media University’ and find out. Scandal was a midseason replacement that found an audience by force feeding these fans who eat it up.”

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ABC also is hoping the Scandal finale boosts Jimmy Kimmel’s late-night talker tonight. Rhimes will hold court on Jimmy Kimmel Live!, which has built its Thursday nights around the D.C. fixer series as Kimmel battle Jimmy Fallon et al. for late-night supremacy online and off. Throughout the season, the network has cross-promoted “Scandal Thursdays” there. Kimmel is coming back into the studio during a week of reruns to sit down with Rhimes — in what they’re entertainingly calling Behind The Scandalabra.